Q:

Brainliest for correct answer!Which strategy can be used to solve this problem? Dan has dogs named Chester and Ally. Together the two dogs weigh 40 pounds. Chester weighs 4 pounds more than Ally. How much does Ally weigh? A. Write a number sentence. Let p represent the amount that Ally weighs. (4 + 40) ÷ 2 = p B. Guess and test. Guess that Ally weighs 20 pounds. Add 4 to 20 to find out how much Chester weighs (24). Add Chester's and Ally's weights (44). Ask if the sum is more or less than 40. Revise your guess so it is 19 and test your answer again. Repeat the process until you have the correct answer. C. Draw a diagram. Draw 40 dots to represent how much the two dogs weigh altogether. Divide the dots into 2 equal groups and then divide one of the groups by 4.

Accepted Solution

A:
Let
C = weight of Chester
A = weight of Ally

From the information given,
Both dogs weigh 40  pounds. Therefore,
C + A = 40 --- (1)

In addition, Chester weighs 4 pounds more than Ally. Therefore,
C = A + 4 ---- (2)

Substituting for C from equation (2) in equation (1);
A + 4 + A = 40
2A + 4 = 40
2A = 40 -4 = 36
2A = 36
A = 36/2
A = 18 pounds

Therefore, Ally weighs 18 pounds.