To find the length of a right rectangular prism, you can use the formula for the volume of a rectangular prism:
\[ \text{Volume} = \text{Length} \times \text{Width} \times \text{Height} \]
Given:
- Volume = 90
- Width = 3
- Height = 5
You can rearrange the formula to solve for Length:
\[ \text{Length} = \frac{\text{Volume}}{\text{Width} \times \text{Height}} \]
Substituting the known values:
\[ \text{Length} = \frac{90}{3 \times 5} \]
Calculating the denominator:
\[ 3 \times 5 = 15 \]
Now calculating the Length:
\[ \text{Length} = \frac{90}{15} = 6 \]
So, the length of the right rectangular prism is 6.