Using 1 cup = 240 mL, what volume is 7 cups?

### Why this is right Each cup contains $240\ \text{mL}$, so seven cups contain $7\times240=1{,}680\ \text{mL}$. The cup unit cancels when the conversion factor is written as $240\ \text{mL}/\text{cup}$. ### The concept For a direct conversion, multiply the number of starting units by the amount in one starting unit. Keep the unit in the calculation to confirm that the result is in millilitres rather than cups. ### The other options - **A. 1,440 mL**: this is $6\times240$, as if one cup were omitted. - **C. 1,920 mL**: this is $8\times240$, as if an extra cup were added. - **D. 2,400 mL**: this is $10\times240$, not seven cups. ### Worked numbers - **Given**: $7\ \text{cups}$ and $1\ \text{cup}=240\ \text{mL}$. - **Find**: volume in millilitres. - **Convert**: $240\ \text{mL}/\text{cup}$. - **Solve**: $7\ \text{cups}\times240\ \text{mL}/\text{cup}=1{,}680\ \text{mL}$. - **Answer**: $1{,}680\ \text{mL}$. - **Check**: cups cancel, leaving millilitres. ### Terms - **Cup**: a volume unit used in the supplied exercise. - **Millilitre (mL)**: a metric unit of volume. ### Remember Multiply the number of cups by 240 to obtain millilitres.