Question

Quinn needs to collect at least 90 toys for a toy drive to earn community service credit. He has already collected 16 toys.

Answer 1

Let's define the next variable:

t: number of toys that Quinn still needs to collect

The number of toys that he already collected plus the number of toys that Quinn still needs to collect is: 16 + t

Quinn needs to collect at least 90 toys, then 16 + t must be greater than or equal to 90, that is,

16 + t ≥ 90

or

90 ≤ 16 + t

Subtracting 16 at both sides, we get:

90 - 16 ≤ 16 + t - 16

74 ≤ t