©mp.4 model with math
when mary was born, she weighed 8 pounds. when she was 10 years old, she weighed
10 times as much. how much more did mary weigh when she was 10 years old than
when she was born? use exercises 1-2 to answer the question.
1. draw a picture, write and solve an equation to find mary's
weight, w, when she was 10 years old.
2. draw a picture, and write and solve an equation to find the
difference, d, between mary's weight when she was 10 years
old and when she was born.

The drawings are in the picture attached and the explanations are below.

Question 1.

Question 2:

Explanation:

Question 1:

                              w = 10 × 8 lbs = 80 lbs

Explanation of the drawing:

Each cell represents 8 lbs, which was the weight when she was born. There are 10 cells, representing that the amount 8 lbs is repeated 10 times.

Then, the multiplication is represented  an abbreviated sum:

Question 2:

        d         =          80 lbs   -     8 lbs   =       72 lbs

        ↑                       ↑                  ↑                  ↑

 difference       10 years old      born          solution

Explanation of the drawing:

10

step-by-step explanation:

the revenue of the fitness center, y, is the product of two factors: the number of members and the fee paid by each member. there are 320 members now, but number of members goes down by 10 for each $5 increase in fees, so if x is the number of $5 price increases then members is equal to (320 - 10x). since the fee is currently $45, and the fee increases by $5 for every price bump x, the fee is given by (45 + 5x). so, revenue y is given by y = (320 - 10x)(45 + 5x).