Respuesta :
Answer: 14 butterflies per hour
Step-by-step explanation: "Per hour" means in 1 hour so we can rewrite the given statement using fractions.
42 butterflies over 3 hours = ___ butterflies per hour.
I have attached my work in the image provided.
To find out what goes in the blank, notice that we have a 1 in the denominator of our second fraction. So we want to find a fraction that is equivalent to 42/3 that has a 1 in the denominator.
If we divide the numerator and denominator of 42/3 by 3, we get the equivalent fraction 14/1 or 14 butterflies over 1 hour. So now we have 14 butterflies over 1 hour = ___ butterflies per hour.
Now we can easily see that a 14 must go in the blank which means that the unit rate for 42 butterflies in 3 hours is 14 butterflies per hour.