He did not because he only used less than half of the students in the school in the survey. if you want a efficient and accurate survey, ask all the students in the school.

a 4/6 = 9/12   not proportional

step-by-step explanation:

to find which are not proportional, we can use cross products

if it is true, they are proportional.   if it is not true, they are not proportional.

a 4/6 = 9/12

4* 12 = 6*9

48 = 54

not this is not proportional  

b 2/3 = 12/18  

2* 18 = 3 * 12

36 = 36

this is proportional

c 5/4 = 10/8  

5*8 = 4*10

40 = 40

this is proportional

d 7/5 = 35/25

7*25 = 5 * 35

175 = 175

is proportional

191 students play sports and ninety-seven 10th graders were surveyed.

step-by-step explanation:

the correct answer option is d. la = πrs.

step-by-step explanation:

we know that for a right cone, the lateral surface area is given by:

lateral area of right cone =

here the value under the square root is equal to slant height so replacing this value by in the formula to get:

lateral area of right cone =

therefore, the correct answer option is d.