Answer:
85.7
Step-by-step explanation:
Given that two sections of a class took the same quiz. Section A had 15 students who had a mean score of 80, and Section B had 20 students who had a mean score of 90.
Section A total score = 15*80=1200
Section B total score 20*90 = 1800
Overall total score=3000
Overall total students = 15+20 =35
Hence overall mean = 
rounding off to one decimal place
overall mean = 85.7
Radius is 15 cm
Circumference = 2 pi r
C = 2 x 3.14 x 15cm
C = 94.2 cm
94.2 cm x 4 (revolutions) = 376.8 = D
Answer: (y*40)+(y*8)
Step-by-step explanation:
Hopes this helps:
Answer: x = -10/7
1. Simplify 2 • 2 to 4
4 + 7x + 6 = 0
2. Simplify 4 + 7x + 6 to 7x + 10.
7x + 10 = 0
3. Subtract 10 from both sides.
7x = -10
4. Divide both sides by 7.
X = -10/7