Solve proportions: word problems
Learn with an example
✏️ Shelley took a total of 10 pages of notes during 5 hours of class. After attending 6 hours of class, how many total pages of notes will Shelley have in her notebook? Assume the relationship is directly proportional.
______ pages
Set up a proportion and solve for n.
10 pages / 5 hours = n pages / 6 hours
10 / 5 ( 5 . 6 ) = n /6 ( 5 . 6 ) Multiply both sides by 5 · 6
10 · 6 = 5n Simplify
60 = 5n Multiply
12 = n Divide both sides by 5
After attending 6 hours of class, Shelley will have a total of 12 pages of notes in her notebook.
✏️ Rob jarred 4 litres of jam after 2 days. How many days does Rob need to spend making jam if he wants to jar 6 litres of jam in all? Assume the relationship is directly proportional.
_____ days
Set up a proportion and solve for n.
4 litres / 2 days = 6 litres / n days
4/2 ( 2n ) = 6/n ( 2n ) Multiply both sides by 2n
4n = 6 · 2 Simplify
4n = 12 Multiply
n = 3 Divide both sides by 4
If Rob wants to jar 6 litres of jam, he will need to spend 3 days making jam.
✏️ Cameron prepared 16 kilograms of dough after working 2 hours. How much dough did Cameron prepare if he worked for 6 hours? Assume the relationship is directly proportional.
______ kilograms
Set up a proportion and solve for n.
16 kilograms / 2 hours = n kilograms / 6 hours
16/2 ( 2 . 6 ) = n/6 ( 2 . 6 ) Multiply both sides by 2 · 6
16 · 6 = 2n Simplify
96 = 2n Multiply
48 = n Divide both sides by 2
If Cameron worked for 6 hours, he prepared 48 kilograms of dough.
let’s practice! 🖊️
