Question

Hans baked b cookies. His family ate 20 of them. Using b, write an expression for the number of cookies that remained.

Answer 1

$\text{number of cookies that remained = }b\text{ - 20 }$Explanation:

Number of cookies = b

Number of cookies the family ate = 20

number of cookies left = ?

Number of cookies = Number of cookies ate + number of cookies that remained

b = 20 + number of cookies that remained

To get the number of cookies that remained, we'll subtract 20 from both sides:

$\begin{gathered} b\text{ - 20 = 20 - 20 + number of cookies that remained} \\ b\text{ - 20 = number of cookies that remained} \end{gathered}$

An expression showing number of cookies remaining:

$\text{number of cookies that remained = }b\text{ - 20 }$