A random sample of students were chosen from all of 7th grade. There were 3 boys and 5 girls in that sample. If there are a total of 240 students on campus, how many students might be boys?

90

Step-by-step explanation:

3 boys

5 girls,

Say that there where "x" number of groups like this, (x will be the total number of groups like this, if one were to divide the population by the number of groups, they would the number of students);

Set up an equation;

x ( 3 + 5 ) = 240

Combine like terms and distribute;

8x = 240

Inverse operations;

8x = 240

/8        /8

x = 30

Substitute back in to find the number of boys;

30 * 3 = 90

60

step-by-step explanation:

question 1 is 8, question 2 is 9, question 3 is 24

step-by-step explanation:

now, the numbers they give you at the top are the key. from there, you just have to plug and chug! let's try 1, 2, and 3!

key: a=3, b=5, c=6

1. a+5

remember, a=3, so we plug that in to get 3+5=8

2. 15-c

c=6, so we plug that in to get 15-6=9

3. 4b

b=6, so we plug it in to get 4*6=24

time to try the rest on your own! if you put the answers below in a comment, i'll check them for you!