Question

evans favorite hobby is origami. he plans to make 100 paper cranes to hang from the ceiling of his bedroom. yesterday, he made 28 paper cranes in 4 hours. today, he made 21 paper cranes at the same rate. how long did evan spend making paper cranes today? hours submit

Explanation:

Step1: Find the rate of making cranes

First, we find the rate at which Evan makes paper cranes. Yesterday, he made 28 cranes in 4 hours. So the rate is the number of cranes per hour, which is calculated by dividing the number of cranes by the number of hours. So the rate \( r=\frac{28}{4} = 7 \) cranes per hour.

Step2: Calculate time for 21 cranes

Today, he made 21 cranes at the same rate. To find the time, we use the formula \( \text{time}=\frac{\text{number of cranes}}{\text{rate}} \). We know the number of cranes is 21 and the rate is 7 cranes per hour. So the time \( t=\frac{21}{7}=3 \) hours.

Answer:

3