Now consider just the second sentence of the multistep word problem.

Question

Sentence 2: If four times the brother's age is subtracted from three times the sister's age, the difference is 16.
Give an equation that represents this statement using b as the age of the brother and s as the age of the sister.
Using your answers from parts B and C, what are the ages of the brother and sister, respectively?

Answer 1

when solving for multiple variables
... you need as many unique equations , as there are unknowns
... in this case , two

at present, there is insufficient information for a solution

Answer 2

This sentence says that:
3s-4b = 16
I assume you have other information from previous parts. Use this and that to find what you need.

Answer 3

This is a chemistry problem? Looks pretty math-y to me.