Answer: 1, 2, 4, 8 or 16 t-shirts.
Explanation:
1. To solve this problem you can find the factor pairs of 16.
2. By definition, factor pairs are two whole numbers that are multiplied to obtained a determined product.
3. Therefore, keeping the information above on mind, you must write the factor pairs whose product is 16. You have:
- She could have bought 1 t-shirt with a cost of $16:
![1*16=16](https://img.qammunity.org/2019/formulas/mathematics/high-school/s22j4jq1auphuf2jqzbx0gpne5nf7t593s.png)
- She could have bought 2 t-shirts, each one with a cost of $8:
![2*8=16](https://img.qammunity.org/2019/formulas/mathematics/high-school/m56xnhmb8syia4vwvyemurop77bw3qn0yb.png)
- She could have bought 4 t-shirts, each one with a cost of $4:
![4*4=16](https://img.qammunity.org/2019/formulas/mathematics/high-school/zrkaoffrypih9z13vl8mqt47zbd90kj4pv.png)
- She could have bought 8 t-shirts, each one with a cost of $2:
![8*2=16](https://img.qammunity.org/2019/formulas/mathematics/high-school/fqpxvfkccd1gl4j7h6yy2xk38s1g4khh9t.png)
- She could have bought 16 t-shirts, each one with a cost of $1: