Question

jill can make 50 flash cards every 20 minutes. complete the table using equivalent ratios. minutes number of cards 20 50 30 36

Explanation:

Step1: Find the rate

The rate of making flash cards is $\frac{50}{20}=\frac{5}{2}$ cards per minute.

Step2: Find minutes for 30 cards

Let $x$ be the minutes for 30 cards. We have the ratio $\frac{50}{20}=\frac{30}{x}$. Cross - multiply: $50x = 20\times30$. Then $x=\frac{20\times30}{50}=\frac{600}{50} = 12$.

Step3: Find cards in 36 minutes

Let $y$ be the number of cards in 36 minutes. Using the ratio $\frac{50}{20}=\frac{y}{36}$. Cross - multiply: $20y=50\times36$. Then $y = \frac{50\times36}{20}=\frac{1800}{20}=90$.

Answer:

For 30 cards, the number of minutes is 12. For 36 minutes, the number of cards is 90. So the completed table has 12 in the minutes column for 30 cards and 90 in the number of cards column for 36 minutes.