Gillian paid $30 for 3 blouses and 5 sweaters. Three blouses cost as much as five sweaters.
- Find the cost of one blouse.
- Find the total cost of 3 blouses and 5 sweaters.
(a)
Cost of 3 blouses = Cost of 5 sweaters
LCM of 5 and 3 = 15
Cost of 3 blouses = 15 u
Cost of 1 blouse = 15 u ÷ 3 = 5 u
Cost of 5 sweaters = 15 u
Cost of 1 sweater = 15 u ÷ 5 = 3 u
Cost of 3 blouses
= 3 x 5 u
= 15 u
Cost of 5 sweaters
= 5 x 3 u
= 15 u
Cost of 3 blouses and 5 sweaters
= 15 u + 15 u
= 30 u
30 u = 30
1 u = 30 ÷ 30 = 1
Cost of one blouse
= 5 u
= 5 x 1
= $5
(b)
Cost of 1 sweater
= 3 u
= 3 x 1
= $3
Total cost of 3 blouses and 5 sweaters
= 3 x 5 + 5 x 3
= 15 + 15
= $30
Answer(s): (a) $5; (b) $30
