Starting with some solution of volume v and an alcohol concentration of 100c % , if you add 180 mL of 45% isopropyl to it, you get a mixture with a total volume of 180 mL + v.
Each mL of the starting solution contains c mL of alcohol. For example, if the concentration of the starting solution is 80% (so c = 0.8), then each mL contains 80% = 0.8 of one mL of alcohol.
Similarly, each mL of the added solution with 45% concentration contains 0.45 mL of alcohol.
You want the new solution to have a concentration of 70%, so that the ratio of the amount of alcohol in it to the total volume is 70%, meaning
cv + 0.45 (180 mL) = 0.7 (180 mL + v)
and you want to solve for v :
cv + 81 mL = 126 mL + 0.7v
cv - 0.7v = 126 mL - 81 mL
(c - 0.7) v = 45 mL
v = (45 mL) / (c - 0.7)
Judging by context clues, c lies somewhere between 0.7 and 1. (It can't be less than 0.7 because mixing this solution with any other solution of smaller concentration will never yield a solution of higher concentration.)
If, for example, c = 0.8, so that your starting solution is at 80% concentration, then you would need
v = (45 mL) / (0.8 - 0.7) = 450 mL
to be mixed with 180 mL of 45% solution to end up with 180 mL + 450 mL = 630 mL of 70% solution.
As another example, if you're mixing pure alcohol, so that c = 1, you would need
v = (45 mL) / (1 - 0.7) = 150 mL
to make a 180 mL + 150 mL = 330 mL batch of 70% solution. The fact that you would need less of a higher concentration solution is not surprising.
HELP PLEASE!!
40 POINTS FOR BOTH QUESTIONS
please please
Answer:
1. Angle Bisector Theorem
(2x-1)/3x=9/15
15(2x-1)=9(3x)
30x-15=27x
3x=15
x=5
2. Triangles are similar so the ratio that relates them is 6/36=1/6 meaning the side length is 42x1/6=7 cm.
How do I graph these parabolas
solve
log5(2)+log5(x)-log5(x-1)=log5(3)
Step-by-step explanation:
log5(2)+log5(x)-log5(x-1)=log5(3)
log5(2x) = log5(3)+log5(x-1)
log5(2x) = log5(3Xx-1)
2x = 3x-3
x= 3
Consider a collection of envelopes consisting of 3 red , 3 blue , 1 green , and 2yellow . If three envelopes are selected at random, without replacement, determine the probability that at least one envelope is a red envelope.
Answer:
The probability is 31/35
Step-by-step explanation:
Gabby accumulated $12,000 in credit card debt. If the interest rate is 4% per year and she does not make any payments for 8 years, how much will she owe on this debt in 8 years by compounding continuously?
Answer:
$16,525.53.
Step-by-step explanation:
A=Pe^rt
P=$12,000
r=0.04
t=8 years
true or fales: a significant correlation indicates that changes in the values of one factie cause changes in the values of a second factor
Answer:
A significant correlation means that there is a significant (in a statistical point of view) correlation between two things.
Then a significant correlation means that we have a (measurable) correlation between the variables in our experiment.
Now, the factors are the variables that experimenters control during an experiment in order to determine their effect on the response variable, then having a positive correlation between two factors, means that when we change one, the other is also affected by the change in the first one.
Then the statement is true.
Kai is looking for his first job as a pharmacy technician. He prepares for the job by memorizing household, metric, and apothecary abbreviations. In addition, he memorizes the methods for converting data between those measurement systems. Perform the following calculation using the ratio and proportion method. How many ounces (oz) are equal to 4 cups?
Answer:
Step-by-step explanation:
0.5: 4
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There are 45 students who play a woodwind instrument in the school band. Of these, 18 play the saxophone. What percent of the woodwind musicians play the saxophone?
how many grams in 1.7x 10^7 ug
Answer:
17 grams
Step-by-step explanation:
a cow heart beat 325 in 5 minutes. about how many times does a cow's heart beat in 2 minutes?
Answer:
130
Step-by-step explanation:
You can make a ratio - 325:5, then we can simplify it to 65:1, where we are comparing # of beats in 1 minute. Now, we can just multiply both sides by two, getting us 130:2, which is just 130 beats.
Convert 1.05 to a percent.
Answer:
105%
Step-by-step explanation:
you would just move the decimal 2 places to the right
10+10 Chloe answer
Answer:
20
Step-by-step explanation:
Solve. Explain your answers in the box below.
a. Travis estimated the product of 602 and 341 to be 1,800. His work is shown below. Find and explain Travis's error.
600×300
6 hundreds × 3 hundreds =18 hundreds
600×300=1,800
b. Margaret said the exact product of 602 and 341 is 205,282. Is she correct? Use paper and the standard algorithm to support your reasoning.
Answer:
Travis estimated the product of 602 and 341 to be 1,800. His work is shown below. Find and explain Travis's error. 600×300 6 hundreds × 3 hundreds =18 hundreds 600×300=1,800 b. Margaret said the exact product of 602
Step-by-step explanation:
i hoped it was right!
Figure LMNO maps to L'M'N'O' by a 125° rotation about point T.
Quadrilateral L M N O is rotated 125 degrees about point T to form quadrilateral L prime M prime N prime O prime.
Which congruency statement is correct?
LMNO ≅ L'M'N'O'
LMNO ≅ O'M'N'L'
ONML ≅ M'O'N'L'
ONML ≅ O'M'N'L'
Answer:
A= LMNO ≅ L'M'N'O'
Step-by-step explanation:
just did it trust me
A= LMNO ≅ L'M'N'O'. Hope this helps!!
I need help on this
Answer:
,b j,mbnlvj lcv
Step-by-step explanation:
nb ckhbv m
i just want want points sorry! :)
At the local sandwich shop, employees earn double time for any hours worked in addition to their regular 39-hour
week. Last week, Cooper Jones worked his regular 39 hours plus 9 hours of overtime. Cooper is paid $23.90 per
hour. What is his total pay for the week?
Answer:
8,030.4
Step-by-step explanation:
Answer:
$287.04
Step-by-step explanation:
add 39 and 9 multiply the sum by $23.90 and then multiply by two and boom, $287.04
A product is marked down 15%; the sale price is $127.46. What
was the original price?
Answer: $ 149.95.
Step-by-step explanation:A product is marked down 15%; the sale price is $127.46. What was the original price? Substitute 127.46 for S.P and 15 for m in (1). So, the original price is $ 149.95.
The original price of the product will be $149.95.
What is the percentage?The quantity of anything is stated as though it were a fraction of a hundred.
A product is marked down 15%.
The sale price is $127.46.
Then the original price of the product will be
Let x be the original price.
(1 – 0.15)x = $127.46
0.85x = $127.46
x = $149.95
More about the percentage link is given below.
https://brainly.com/question/8011401
#SPJ2
If ∠BAC ≅ ∠DCA, is ABE ≅ CDE? Explain.
A. Yes; the triangles are congruent by AAS.
B. Yes; the triangles are congruent by ASA.
C. Yes; the triangles are congruent by SAS.
D. No; the triangles are not congruent.
Answer:
The answer is A.
Step-by-step explanation:
It is A because both sides match up except for the last pair, where they are the same. Hope this helped!
Explain how to use the distributive property to find the product (3) ( 4 /1 5 )
Answer:
Reduce the expression, if possible, by cancelling the common factors.
the answer is 4/5 or 0.8 :)
Step-by-step explanation:
Answer:
Sample Response: Rewrite 3 ( 4 1/5) as 3 ( 4 + 1/5 ). Distribute the 3 to get 3(4) + 3 (1 /5 ) . Multiply to get 12 + 3 /5 . Then add to get 12 3 /5 .
Please help and tell me why you got that answer! :)
Answer: A.
Step-by-step explanation: The fashion express magazine having 4,880 subscribers and losing 300 times something lines up with that in the expression. And the new trends magazine having 3,140 and gaining 280 times something lines up with the expression. The expression is also suppose to be equal and the word problem is asking for when the subscriber count would be equal. Solving the expression using the word problem would have you end up with m = 3, so in 3 months they will have equal subscribers (aka both will have 3,980 subscribers)
Tuition for one year at the University of Houston is about $12,300. Azul plans to attend this university and will save money each month for the next 4 years. His parents have saved $4,860 for his first year of tuition. Which plan shows the amount of money Azul will need to save in order to pay for his first year at the University of Houston?
A. Azul will need to save $1,860 per month for the next 4 years.
B. Azul will need to save $155 per month for the next 4 years.
C. Azul will need to save $620 per month for the next 4 years.
D. Azul will need to save $256.25 per month for the next 4 years
Answer:
It should be C. 620
Step-by-step explanation:
Using proportions, it is found that Azul will need to save $155 per month for the next 4 years, and the correct option is B.
The total price of one year of tuition is $12,300, while his parents have saved $4,860.Thus, the amount he has to save for the next 4 years is:
[tex]A = 12300 - 4860 = 7440[/tex]
4 years have 48 months, thus, he has to save $7440 in 48 months, which means that the monthly amount is:[tex]\frac{7440}{48} = 155[/tex]
And the correct option is:
B. Azul will need to save $155 per month for the next 4 years.
A similar problem is given at https://brainly.com/question/24342347
6.8x+9.3= -9.4+3.4(2-5x)
Answer: the answer to this is x=0.5
Step-by-step explanation:
In order to solve this you have to combine the multiplied terms into a single fraction so its going to look like this - 34x/5 + 9.3= -9.4+3.4(2-5x)
The reposition your terms and put together your multiplied terms into a fraction,Once you have that done distribute them
Subtract 9.3 on both sides.you may simplify and then multiply all the terms with the same value to get rid of the denominators from the fractions
also add 85x to both sides then finally divide both side by the same term which get you -59.5/119 and then simplify and you get -0.5
so x= -0.5
Answer:
x=-0.5
Step-by-step explanation:
step 1
6.8x+9.3=-9.4+3.4(2-5x)
6.8x+9.3=-9.4+(3.4)(2)+(3.4)(-5x) distribute
6.8x+9.3=-9.4+6.8+-17x
6.8x+9.3=(-17x)+(-9.4+6.8) combine like terms
6.8x+9.3=-17x+-2.6
6.8x+9.3=-17x-2.6
step 2
add 17x to both sides.
6.8x+9.3+17x=-17x2.6+17x
23.8x+9.3=-2.6
step 3
subtract 9.3 from both sides.
23.8x+9.3-9.3=-2.6-9.3
23.8x=-119
step 4
divide both sides by 23.8
23.8x/23.8= -11.9/23.8
The answer is =-0.5
Examine the system of equations.
y = negative one-fourth x minus 2
x = 4
What is the solution to the system?
(–3, –2)
(4, –3)
(4, –2)
(4, –1)
The answer is 4,-3
Irfcdxsaacd d
Answer:
4,-3
Step-by-step explanation:
each small square in the graph paper represents 1 square unit. tap picture.
Answer: The answer is 96 square units.
Step-by-step explanation:
(Because it's 8 square units long and 12 square units wide. L x W = Area)
So you have to do 12 x 8 and you should get the answer 96 square units.
If C is the midpoint of BD, what is the coordinate of point C if point B is at 0?
Answer:
It depends on where point D is placed so C > 0
Step-by-step explanation:
As i said above
We want to find the coordinate of C given that it is the midpoint of BD.
We know that B is at 0, so we can assume that each letter represents a position on the number line.
Then we can assume that D is located at a number different than zero, let's assume that D is located at the value d.
Then the segment BD goes from 0 to d, so its length is d.
Then the midpoint is at the middle, at d/2 plus the smallest value, 0:
C = d/2 + 0 = d/2
If you want to learn more, you can read:
https://brainly.com/question/2441957
The vertex of a parabola is (6,2), and the equation of its directrix is x = 8. What is the equation of this parabola in standard form?
a. (y−2)2=8(x−6)
b. (y−2)2=−8(x−6)
c. (x−6)2=−8(y−2)
d. (x−6)2=8(y−2)
Answer:
The equation of this parabola in standard form is (y - 2)² = -8(x - 6) ⇒ B
Step-by-step explanation:
Let us revise the standard form of the equation of a parabola
The standard form of the equation is (y - k)² = 4p(x - h), where
(h, k) is the turning point (h + p, k) are the coordinates of the focus x = h - p is the equation of the directrix
∵ The vertex of a parabola is (6, 2)
→ From the fact above
∴ h = 6 and k = 2
∵ The equation of its directrix is x = 8
→ From the fact above
∴ h - p = 8
→ Substitute the value of h to find p
∵ 6 - p = 8
→ Subtract 6 from both sides
∴ - p = 2
→ Multiply both sides by -1
∴ p = -2
→ Substitute the values of h, k, and p in the form above
∴ (y - 2)² = 4(-2)(x - 6)
∴ (y - 2)² = -8(x - 6)
∴ The equation of this parabola in standard form is (y - 2)² = -8(x - 6)
Which of the following is a true statement concerning the use of a placebo?
A.
B.
C.
D.
Answer:
its B
Step-by-step explanation:
reflecting the graph of y = cos x across the y-axis is the same as not reflecting it at all
Answer:
The graph of the equation x2+y2=0 in the three dimensional space is (A) x-axis (B) y-axis (C) z-axis (D) xy-plane
Step-by-step explanation:
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HELP ASAP
Find the 15th term or the geometric sequence 7, -21, 63,
33480783
Step-by-step explanation:Finding the Common Ratio:
We know that the formula for the common ratio of a GP is:
r = aₙ / (aₙ₋₁) (Where n is any integer)
replacing the values, taking n=2
r = -21 / 7
r = -3
Solving for the 15th Term:
We know that the Formula for the nth term of a GP:
G(n) = a * r ⁿ⁻¹ (where a is the first term and r is the common ratio)
replacing the values (taking n = 15 since we need the 15th term)
G(15) = 7 * (-3)¹⁴
G(15) = 33480783
Hence, the 15th term of the given GP is 33480783
Please help! I’ll mark you as brainliest if correct!!!!
Answer:
20Step-by-step explanation:
The equation of shifted function y = ax² is y = a(x-h)²+k, where h tells us how many units we move left (h<0) or right (h>0) and k tells how many units up (k>0) or down (k<0)
y = x² - 20 = 1(x - 0)² + (-20) ⇒ k = -20<0
So it's shifted 20 units down.