PSLE At a sale, Luke bought 11 mugs of the same kind. His cousin bought 7 such mugs. She also bought 4 cups at $5.10 each. Altogether, she spent $2.80 less than Luke. What was the total amount of money Luke and his cousin spent?
|
Luke |
His cousin |
Items bought
|
11 mugs
|
7 mugs + 4 cups = 7 mugs + 20.40 |
Comparing the amounts paid |
$2.80 more |
|
Amount that his cousin spent on 4 cups
= 4 x 5.10
= $20.40
Let the cost of 1 mug be 1 M.
If Luke spent $2.80 less, each would pay the same amount.
11 M - 2.80 = 7 M + 20.40
11 M - 7 M = 20.40 + 2.80
11 M - 7 M = 23.20
4 M = 23.20
1 M = 23.20 ÷ 4 = 5.80
Total amount that Luke and his cousin spent
= 11 M + 7 M + 20.40
= 18 M + 20.40
= 18 x 5.80 + 20.40
= 104.40 + 20.40
= $124.80
Answer(s): $124.80