If Sally takes a 20 minute piano lesson this week, how many many minutes should she practice this week?

Question

Her goal is to pract piano 20 minutes for every 5 minutes of lessons she takes.

Answer 1

20/5 = 4 (She took a 20 min lesson, and plans to have practice sessions per 5 minutes of lesson)

4 * 20 = 80 (each practice is 20 min long and she practices 4 times)

80 minutes of practicing.

 

Our problem can also look like this if we want to combine the steps into one whole problem:

²⁰/₅ * 20

Answer 2

every 5 minutes of piano lessons she has to practice 20 mins so our k or constant of proportionality is

 

5k = 20

 

k = 4

 

so for a 20 min piano lesson her practice ought to be = 20 k

 

= 20 *4

 

= 80 minutes