PSLE At a sale, Andy bought 9 glasses of the same kind. His sister bought 6 such glasses. She also bought 3 mugs at $1.60 each. Altogether, she spent $14.10 less than Andy. What was the total amount of money Andy and his sister spent?
|
Andy |
His sister |
Items bought
|
9 glasses
|
6 glasses + 3 mugs = 6 glasses + 4.80 |
Comparing the amounts paid |
$14.10 more |
|
Amount that his sister spent on 3 mugs
= 3 x 1.60
= $4.80
Let the cost of 1 glass be 1 G.
If Andy spent $14.10 less, each would pay the same amount.
9 G - 14.10 = 6 G + 4.80
9 G - 6 G = 4.80 + 14.10
9 G - 6 G = 18.90
3 G = 18.90
1 G = 18.90 ÷ 3 = 6.30
Total amount that Andy and his sister spent
= 9 G + 6 G + 4.80
= 15 G + 4.80
= 15 x 6.30 + 4.80
= 94.50 + 4.80
= $99.30
Answer(s): $99.30