Mrs. morton has a special reward system for her class. when all her students behave well, she rewards them by putting 3 marbles into a marble jar. when the jar has 100 marbles or more, the class has a party. right now, the jar contains 24
marbles.

This an example problem of arithmetic progression. Where there is a common of difference of 3. So the  formula

X = a1 + (n-1) d

Where x = 102 ( because is the first number greater than 100 that is divisible by 3

A1 = is the current amount of marble

N = number of times they need to behave

D = 3

102 = 24 + (n-2) 3

Solving for n = 27 times they need to behave

5x+40

5(x + 8)

7x - 49

7(x - 7)

18x + 9

9(2x + 1)

15x - 10

5(3x - 2)

step-by-step explanation:

for number one all you have to do is factor 5 out of 5x + 40

for number 2 factor 7 out of 7x - 49

for number three factor 9 out of 18x + 9

for number four factor 5 out of 15x - 10