Answer:
D
PLZ MARK AS BRAINLIEST
Step-by-step explanation:
FIRST STEP:
4*3 =12
6.5*3 =19.5
SECOND STEP:
21*12*19.5 =4914
Answer:
The mean score for all students on the quiz was 86.
Step-by-step explanation:
This question is solved by a weighed average.
To find the weighed average, we add the values multiplied by their weight, and after that we divide by the sum of weights.
In this problem, we have that:
Mr. Spears had 20 students in his class with a mean score of 80.
So 80 has a weight of 20.
Mrs. Guyton's class of 30 students had a mean score of 90.
So 90 has a weight of 30.
Overall, what was the mean score for all students on the quiz

The mean score for all students on the quiz was 86.
Answer: 3.2
Just divide 400 by 125 because the opposite of multiplication is division.
When you divide you get 3.2
Answer:
13
Step-by-step explanation:
Parentheses first:
5+ (-4) * (-2)
Then Multiply:
5+8
Then Add:
13
Answer:
A). PR = 16.13 ft
B). QR = 9.64 ft
Step-by-step explanation:
Part (A).
From the figure attached,
ΔPQR is a right triangle,
m(PQ) = 14 ft
m(QR) = 8 ft
By applying Pythagoras theorem,
Hypotenuse² = (Leg 1)² + (Leg 2)²
(PR)² = (PQ)² + (QR)²
(PR)² = (14)² + (8)²
PR = √260
= 16.125
≈ 16.13 ft
Part (B).
If PR = 17 feet
and PQ = 14 feet
By applying Pythagoras theorem in ΔPQR,
PR² = PQ² + QR²
(17)² = (14)² + (QR)²
(QR)² = 289 - 196
QR = √93
= 9.644
≈ 9.64 ft