All categories

3 years ago

Four friends are told that the average (mean) of their grades for their favorite class is 83.75%.

Mathematics

2 answers:

taurus [48]3 years ago

8 0

Answer:

Step-by-step explanation:

The sum of the 4 grades equals 4 times the average

94 + 78 + 83 + T = 4 * 83.75

94 + 78 + 83 + T = 335

255 + T = 335

Subtract 255 from both sides

T = 80

MrMuchimi3 years ago

6 0

Answer:

Tyler got 80%.

Step-by-step explanation:

Represent Tyler's average by t.

Then .94 + .78 + .83 + t

-------------------------- = 83.75%

Multiplying both sides by 4, we get 2.55 + t = 3.35

so that t = 3.35 - 2.55 = 0.80

Tyler got 80%.

You might be interested in

¼c+3d when c and d=7

-Dominant- [34]

Answer:

22.75

Step-by-step explanation:

you substitute the 7 in for c and d. Following PEMDAS, you would then do (1/4) multiplied by 7 and 3 times 7. add those 2 together and you get 22.75 :)

8 0

3 years ago

which of the following sets could be the sides of a right triangle? {2,3, square root 13} {5,5,2 square root 10} {5,12,15}

anastassius [24]

All of these sets meet the requirements of the triangle inequality. The sum of any two numbers in the set is greater than the third one. (You really only need to check that the sum of the smallest two is greater than the largest.)

It can help to resolve the numbers that are only indicated as to value.

√13 ≈ 3.606

2√10 ≈ 6.325

_____

Your comparisons can be ...

2 + 3 = 5 > 3.606 . . . is a triangle

5 + 5 = 10 > 6.325 . . . . . . is a triangle

5 + 12 = 17 > 15 . . . . . . . . is a triangle

8 0

4 years ago

Martin throws a ball straight up in the air. the equation h(t) = -16t^2 + 40t + 5 gives the height of the ball, in feet, t secon

Lisa [10]

Answer:

2.62 seconds

Step-by-step explanation:

Let

t ----> the time in seconds

h(t) ----> he height of the ball, in feet

we have

$h(t)=-16t^2+40t+5$

we know that

When the ball hits the ground, the height is equal to zero

$-16t^2+40t+5=0$

The formula to solve a quadratic equation of the form

$at^{2} +bt+c=0$

is equal to

$t=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$-16t^2+40t+5=0$

$a=-16\\b=40\\c=5$

substitute in the formula

$t=\frac{-40\pm\sqrt{40^{2}-4(-16)(5)}} {2(-16)}$

$t=\frac{-40\pm\sqrt{1,920}} {-32}$

$t=\frac{-40+\sqrt{1,920}} {-32}=-0.12\ sec$

$t=\frac{-40-\sqrt{1,920}} {-32}=2.62\ sec$

therefore

The solution is t=2.62 seconds

4 0

3 years ago

1 /x^−1 in simplest rational form

Allushta [10]

Here is a link to help you find the answer:
https://www.khanacademy.org/math/algebra2/rational-expressions-equations-and-functions/simplify-rati...

Hope this helps!

3 0

3 years ago

How do you write 5x - 4y = 1 in slope intercept form

Alexxandr [17]

First move the 4y to the right and the 1 to the left:

4y=5x-1

Then divide everything by 4:

y=5/4 x - 1/4

7 0

3 years ago

Read 2 more answers