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A baby, a mother, and a dog


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25 lbs

nice work! Please elaborate on your answer.

Basic system of equations with 3 variables...from the statements:

Let b = baby's weight, d = dog's weight, w = woman's weight...

if the mother weighs 100 pounds more than the combined weight of the baby and the dog

EQUATION 1: b + d + 100 = w

the dog weighs 60 percent less than the baby

EQUATION 2: d = 0.4*b

and then from the picture, we know

EQUATION 3: b + d + w = 170

Then just solve the system

Substitute equation 2 into equations 1 and 3:

1) b + 0.4b + 100 = w and 3) b + 0.4b + w = 170

1) 1.4b + 100 = w and 3) 1.4b + w = 170

Then substitute equation 1 into equation 3:

1.4b + 1.4b + 100 = 170

Solve for b:

2.8b = 70

b = 25

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