Xandra paid $87 for 3 cardigans and 5 sweaters. Four cardigans cost as much as three sweaters.
- Find the cost of one cardigan.
- Find the total cost of 3 cardigans and 5 sweaters.
(a)
Cost of 4 cardigans = Cost of 3 sweaters
LCM of 3 and 4 = 12
Cost of 4 cardigans = 12 u
Cost of 1 cardigan = 12 u ÷ 4 = 3 u
Cost of 3 sweaters = 12 u
Cost of 1 sweater = 12 u ÷ 3 = 4 u
Cost of 3 cardigans
= 3 x 3 u
= 9 u
Cost of 5 sweaters
= 5 x 4 u
= 20 u
Cost of 3 cardigans and 5 sweaters
= 9 u + 20 u
= 29 u
29 u = 87
1 u = 87 ÷ 29 = 3
Cost of one cardigan
= 3 u
= 3 x 3
= $9
(b)
Cost of 1 sweater
= 4 u
= 4 x 3
= $12
Total cost of 3 cardigans and 5 sweaters
= 3 x 9 + 5 x 12
= 27 + 60
= $87
Answer(s): (a) $9; (b) $87
