Irene paid $85 for 3 skirts and 4 jackets. Two skirts cost as much as three jackets.
- Find the cost of one skirt.
- Find the total cost of 4 skirts and 3 jackets.
(a)
Cost of 2 skirts = Cost of 3 jackets
LCM of 3 and 2 = 6
Cost of 2 skirts = 6 u
Cost of 1 skirt = 6 u ÷ 2 = 3 u
Cost of 3 jackets = 6 u
Cost of 1 jacket = 6 u ÷ 3 = 2 u
Cost of 3 skirts
= 3 x 3 u
= 9 u
Cost of 4 jackets
= 4 x 2 u
= 8 u
Cost of 3 skirts and 4 jackets
= 9 u + 8 u
= 17 u
17 u = 85
1 u = 85 ÷ 17 = 5
Cost of one skirt
= 3 u
= 3 x 5
= $15
(b)
Cost of 1 jacket
= 2 u
= 2 x 5
= $10
Total cost of 4 skirts and 3 jackets
= 4 x 15 + 3 x 10
= 60 + 30
= $90
Answer(s): (a) $15; (b) $90
