Answer:
Step-by-step explanation:
9kg
mental math again 60x40x2
Answer:
the answer is 4800
Answer:
What is mental math?
Mental math is definitely what it sounds like—doing math in your head. But it’s also more nuanced than that. Being good at mental math tricks doesn’t mean that you’re able to solve 8974387 x 396 in your head instantly; while cool, that wouldn’t be very practical for daily life. So what does mental math mean?
It really just means being able to calculate in your head. It doesn’t mean you can solve every type of problem every time, nor is it a skill that you either “have” or “don’t have”; it’s a skill that you can learn, practice, and improve so that you can solve a bigger range of problems. And mental math certainly doesn’t have to be entirely in your head, either. Jotting down the numbers you need to remember to give you a head start (no pun intended), or writing down your solutions at each “step,” does not negate the “mental”-ness of the math.
Is mental math useful?
Ask this question again next time you’re trying to figure out a tip or doing any kind of construction or home improvement project! And, in addition to handy practical uses, knowing how to do mental math can also just keep your brain sharp and curb your reliance on calculators. Because, come on, doesn’t it feel good to reach for a calculator only to realize, “Wait, I don’t need it!” and figure out the answer in your head? (Spoiler: It does!) Not to mention knowing how to mentally solve small, simple math problems can save you some steps and help you out if you do need to solve a more complicated, difficult problem. There are always going to be some math problems that it would be silly to not solve with a calculator, but, yes, mental math is useful. And if you’re wondering if math itself is useful, math lessons you’ll actually use in real life.
Step-by-step explanation:
6. Jack is x years old
Jill is 8 years older than Jack.
Mary is three times older than Mary.
The Sum of their ages is 67.
(a) Form a simplified equation in terms of x
(b) Solve the equation and work out Rebecca's Mary's and Jill's ages
Answer:
i didn't understand in third line mate
Find the distance between each pair of points in the coordinate plane.
(3,-2) and (2,-1)
Answer:
1.41
Step-by-step explanation:
How is 5 represented in 6.75
Answer:
5 is in the hundreths place :))
Step-by-step explanation:
Answer:
0.05
Step-by-step explanation:
since the place value of the five is beyond the decimal point, and it is the second number beyond the decimal point, so it is in the hundredths place.
What is the standard form of 3.457
Answer:
3.457 is already in standard form.
Step-by-step explanation:
Deandre pays $15.20 for a pack of 8 towels.
Find the unit price in dollars per towel.
If necessary, round your answer to the nearest cent.
Please help
Answer: Each towel costs $1.90
Step-by-step explanation:
$15.20 divided by 8 = $1.90
PLASE ANSWER THIS!! MARKING BRAINLEIST
1. 59049
2. a^12
3. 8a^6
4. 16a^ 10 b^6
5. 9a^4
6. s^6 t^12
7. s^5 / t^5
8. 6561
9. s^2 t^8 / r^2
10. 81a^2 b^6
An automatic teller machine gives you $150 in five and ten-dollar bills. There are two more than twice as many five-dollar bills as there are ten-dollar bills. How many of each denomination are there?
Answer:
There are 7 ten-dollar bills and 16 five-dollar bills.
Step-by-step explanation:
Let's call:
T: Number of ten-dollar bills
F: Number of five-dollar bills
The amount of money withdrawn from the ATM is $150:
10T+5F=150
Dividing by 5:
[tex]2T+F=30\qquad\qquad [1][/tex]
We also know there are two more than twice as many five-dollar bills as there are ten-dollar bills:
[tex]F=2+2T\qquad\qquad [2][/tex]
Substituting [2] into [1]:
2T+2T+2=30
Rearranging:
2T+2T=30-2
Simplifying:
4T=28
Solving:
T=28/4=7
From [2]:
F=2+2*7=2+14=16
There are 7 ten-dollar bills and 16 five-dollar bills.
An airplane is flying overhead at a constant elevation of 4090 ft. A person is viewing the plane from a position 3010 ft from the base of a radio tower. The airplane is flying horizontally away from the person. If the plane is flying at the rate of 700 ft/s, at what rate is the distance between the person and the plane increasing when the plane passes over the radio tower
Answer:
415 ft/s
Step-by-step explanation:
I've attached a diagram showing the triangle formed between the plane, the person and the radio tower.
From the attached diagram, x represents the position between the person and the position on the ground directly below the airplane while s represents the distance between the person and the plane.
The constant elevation remains 4090 ft while the value of x and s varies with time.
Thus, x varies with respect to time as dx/dt while s varies with respect to time as ds/dt.
Now, we are told that the plane is flying at the rate of 700 ft/s. This means that; dx/dt = 700 ft/s
Now we want to find the rate at which the distance between the person and the plane is increasing when the plane passes over the radio tower.
This means that we want to find ds/dt when x = 3010 ft
From pythagoras theorem if x = 3010 ft and the Elevation remains 4090 ft, we can find s as;
s = √(4090² + 3010²)
s = √25788200
s ≈ 5078.21 ft
Since we want to find ds/dt at x = 3010 ft, from the diagram, we can say from pythagoras theorem that;
x² + 4090² = s²
Differentiating x and s with respect to t, we have;
2x(dx/dt) = 2s(ds/dt)
2 will cancel out to give;
x(dx/dt) = s(ds/dt)
ds/dt = (x/s)(dx/dt)
Plugging in 700 for dx/dt, 3010 for x and 5078.21 for s, we have;
ds/dt = (3010/5078.21) × 700
ds/dt ≈ 415 ft/s
Please help thank you
Answer:
1/144
Step-by-step explanation:
You multiply the top and bottom by itself because its to the second and you get rid of the negative because negative multiplied by a negative is positive
The grandpapa car traffic function is shown check although following statements are true of the function
Simplify the algebraic expression by combining like (or similar) terms.
5+9x+2
Answer:
7 + 9x
Step-by-step explanation:
add 5 and 2 and 9x doesn't have a like term so it stays the same
Answer:
9x + 7
Step-by-step explanation:
Like terms are terms that have the same variables and powers. Here, for 9x, there is no other term that is multiplied by x. So, the only terms we can combine is 2 and 5 which leaves us with 9x+7.
b. If this branch of the military changes the height requirements so that all women are eligible except the shortest 1% and the tallest 2%, what are the new height requirements?
Answer:
c
Step-by-step explanation:
Step-by-step explanation:
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please help!!!!!!!!!!!!!!
Answer:
A
Step-by-step explanation:
By solving (x+6)(x-9), we get x^2 - 3x - 54. By looking at our y-intercept, we can see that only option A has the correct intercept.
Answer:
A
Step-by-step explanation:
you want new jeans and there is a sale this week where they are marked down 30%. what is your final cost if the original price is $50?
Answer: 15 dollars
Step-by-step explanation:
0.3 * 50
15 men can dig a ditch in 10 days, how many day
Will 10men take working at the same rate
Answer:
If 10 men dig a ditch in 12 days .
Total man-days required to dig the ditch
= 10 men × 12 days
= 120 man-days
how long would 15 men take to dig it?
No of days required to finish the job by 15 men
= 120 men-days / 15 men
= 8 days
Answer: 8 days will be required to finish the job by 15 men
Step-by-step explanation:
Hope this helps u
Crown me as brainliest:)
What is the equation in slope-intercept form of the line that passes through the points (−12, −4) and (4, 8)?
A. y = −43 − 20
A. , y = −43 − 20
B. y = 43 − 12
B. , y = 43 − 12
C. y = −0.75 − 13
C. , y = −0.75 − 13
D. y = 0.75x +5
D. , y = 0.75x +5
Answer:
Choice D. [tex]y = 0.75\, x + 5[/tex].
Step-by-step explanation:
The general equation for the slope-intercept form of a line in a cartesian plane is [tex]y = m\, x + b[/tex], where:
[tex]m[/tex] is the slope of the line, and[tex]b[/tex] is the [tex]y[/tex]-intercept of the line. (The [tex]y\![/tex]-intercept of a line in a cartesian plane is the [tex]y\!\![/tex]-coordinate of the point where the line intersects the [tex]\! y \![/tex]-axis.)Start by finding the value of [tex]m[/tex]. The slope of a line is equal to its rise-over-run. For the two points in this question:
The "rise" is the [tex]y[/tex]-coordinate of the first point minus that of the second: [tex]\text{rise} = (-4) - 8 = -12[/tex].The "run" is the [tex]x[/tex]-coordinate of the first point minus that of the second. The order of these two points should stay the same: [tex]\text{run} = (-12) - 4 = -16[/tex].Calculate the slope of this line:
[tex]\displaystyle m = \text{slope} = \frac{\text{rise}}{\text{run}} = \frac{-12}{-16} = 0.75[/tex].
The equation of the line becomes:
[tex]y = \underbrace{0.75}_{m}\, x + b[/tex].
Substitute the coordinates of either of the two points to find [tex]b[/tex]. For example, for the first point [tex](12, -4)[/tex], substitute in the following:
[tex]x = -12[/tex], and[tex]y = -4[/tex].The equation becomes:
[tex]-4 = 0.75 \times (-12) + b[/tex].
Solve for the value of [tex]b[/tex]:
[tex]b = 5[/tex].
Hence, the slope-intercept form of this line shall be:
[tex]y = 0.75\, x + 5[/tex].
CHECK PHOTO Intercepts of the graph BE SURE TO BE CORRECT PLEASE no work needed
Answer:
y= (0, .7)
x= (-1.2, 0)
Step-by-step explanation:
r u taking a test?
10
-25 please answer
Answer:
(-15)
Step-by-step explanation:
10-25 = (-15)
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Plz help Plz help
Ella played a math game and had the five cards shown.
7 0 -4 -10
Her score was the sum of the numbers on these five cards. What was Ella’s score?
3
⊝
23
−5
⊝
Not here
Answer:
-7 (Not here)
Step-by-step explanation:
1. A negative plus a negative equals a negative/ a negative minus a positive equals a negative so: -10 -4 = -14
2. -14 + 7 = -7 so your answer is -7 and it's not an answer choice so you would select "Not here"
4.321 × 12.34 AND IF YOU ANSWER YOU GET 10 POINTS JUST PLS HELP
Answer:
53.32114
Step-by-step explanation:
a chemical change creates a new
Answer:
A new substance with new and different physical and chemical properties.
Step-by-step explanation:
Chemical reactions involve combining different substances. The chemical reaction produces a new substance with new and different physical and chemical properties. Matter is never destroyed or created in chemical reactions. The particles of one substance are rearranged to form a new substance.
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An airplane maintaining a constant airspeed takes as long to travel 925 mi with wind as it does to travel 775 mi against the wind. If the wind is blowing at 15 mph, what is the rate of the plane in still air
9514 1404 393
Answer:
170 mph
Step-by-step explanation:
The speed of the airplane can be represented by s. The travel time will be ...
time = distance/speed
925/(s +15) = 775/(s -15)
925(s -15) = 775(s +15)
150s = 25500 . . . . . . . . . add 13875-775s
s = 170
The rate of the plane in still air is 170 mph.
An experiment consists of determining the speed of automobiles on a highway using a radar equipment. The random variable in this experiment is a:
Answer:
the speed value that the radar equipment outputs.
Step-by-step explanation:
A random variable in an experiment is also (and most times the case) called a dependent variable. In this scenario, the random variable would be the speed value that the radar equipment outputs. This is because this value depends on the actual velocity of the cars that pass by the equipment. The faster the car is moving when it passes the radar the higher value will be displayed on the equipment. Therefore, depending completely on the vehicles.
PLZZ ANSWER THE QUESTION
Answer:
c
Step-by-step explanation:
y = mx + b
”m” is the slope, so the slope is -2
”b” is the y - intercept, so the y - intercept is (0 , 1)
Compare: -7 -4
PLEASE HELP ME!
Which shows another way to write 9.54?
O 0.5 + 0.04
O 9+ 0.4 + 0.05
O (9 * 1) + (5 x 0.1) + (4 x 0.01)
O (9 x 0.1) + (5 x 0.01) + (4 x 0.001)
Answer:
It would be C
Step-by-step explanation:
More on Linear Equations & Linear Systems: Question 1
How many solutions does the system of equations below
have?
y - 2x + 2
y-r-1
Select one:
none
infinitely many
O o o o
one
two
Answer:
21
Step-by-step explanation:
600 students are studying in a private
school, the average monthly fee of a
student is Rs. 1200. How much amount for
tax does the school pay to the government
as education service tax at the rate of 1% in
a year? *
Answer:
600 ×1200=720,000
720,000×12=8,640,000
8,640,000×1%=8,640,000÷100%=86,400
86,400 per year
what are the slopes of the two lines?
green has two yellow dots.
Answer:
-7(1/7) = -1
Step-by-step explanation: