Question

Lisa surveyed 60 students at her school and found that 0.85 of the students she surveyed said their favorite class is math. Another 15% of the students she surveyed reported that their favorite class is science. How many more students in the survey prefer math over science?

9
15
35
42

Answer 1

@iambatman @Michele_Laino

Answer 2

please, note that to each percentage correspond a precise number of students

Answer 3

15% = 15 people

Answer 4

for example 15% * 20 people = 3 people

Answer 5

0.85 = 85

Answer 6

so then...

Answer 7

you have to multiply your percentage by the total number of students

Answer 8

15 * 60 = 900

Answer 9

not 15, but 15/100=0.15

Answer 10

so then .85 - .15 = .70?

Answer 11

no, please no 15*60, but 0.15*60=...

Answer 12

= 9

Answer 13

that's right!

Answer 14

so then its a?

Answer 15

now, do the same using other percentage, please!

Answer 16

= 51

Answer 17

well done!

Answer 18

42?

Answer 19

so d

Answer 20

perfect!

Answer 21

If a sprinkler waters 1 over 20 of a lawn in 1 over 5 of an hour, how much time will it take to water the entire lawn?

3 over 20 hour
1 over 4 hour
4 hours
5 hours

Answer 22

d?

Answer 23

every 1 over 5 of hour our sprinkler waters 1 over 20 of lawn, so
after 2*(1 over 5) hour our sprinkler waters 2*( 1 over 20) of lawn
and after 3*(1 over 5) hour, our sprinkler waters 3*(1 over 20) lawn,
and so on...
so?

Answer 24

20*(1 over 20) lawn are watered after 20 *(1 over 5) hour, so?

Answer 25

please try!

Answer 26

so would it be b? i did try!!

Answer 27

no, please what is 20*(1 over 5)?

Answer 28

4

Answer 29

that's right!

Answer 30

so?

Answer 31

oh so then its c... thanks!!!

Answer 32

ok! thanks!!