Sari wrote the equivalent ratios below to convert cups to fluid ounces. How many fluid ounces are in 9 cups? A.64 fluid ounces B.72 fluid ounces C.80 fluid ounces D.81 fluid ounces
The Correct Answer and Explanation is:
To solve this problem, we need to know the conversion factor between cups and fluid ounces.
Conversion Fact:
1 cup = 8 fluid ounces
Sari is converting cups to fluid ounces using equivalent ratios. To find how many fluid ounces are in 9 cups, we multiply:9 cups×8 fluid ounces per cup=72 fluid ounces9 \text{ cups} \times 8 \text{ fluid ounces per cup} = 72 \text{ fluid ounces}9 cups×8 fluid ounces per cup=72 fluid ounces
So, the correct answer is B. 72 fluid ounces.
Explanation:
This problem involves understanding a basic unit conversion in the customary system of measurement. Cups and fluid ounces are commonly used in recipes and cooking measurements. A cup is a larger unit, and fluid ounces are smaller units used to express volume. The conversion between these two is straightforward and should be memorized for efficiency in problem solving.
To convert from cups to fluid ounces, you use multiplication. Since each cup contains 8 fluid ounces, multiplying the number of cups by 8 gives you the total fluid ounces. This relationship can also be expressed as a ratio:cupsfluid ounces=18\frac{cups}{fluid\ ounces} = \frac{1}{8}fluid ouncescups=81
Creating an equivalent ratio for 9 cups gives:9x=18⇒x=9×8=72\frac{9}{x} = \frac{1}{8} \Rightarrow x = 9 \times 8 = 72×9=81⇒x=9×8=72
This shows that when working with conversions, understanding ratios helps maintain consistency across different quantities. If you multiply both parts of a ratio by the same number, you get an equivalent ratio. Sari used this idea to build from 1 cup to 9 cups. Therefore, 9 cups multiplied by 8 gives 72 fluid ounces.
This type of question tests both your knowledge of measurement conversions and your ability to apply multiplication to solve a real-world problem.
