Xuan had four times the number of metallic bricks as Simon. Xuan used all her bricks to build 9 identical houses. Simon used all his bricks to build 3 identical houses. Xuan used 9 more bricks than Simon for each house. How many bricks did Simon have?
| |
Xuan |
Simon |
| Number |
9 |
3 |
| Value |
1 u + 9 |
1 u |
| Total value |
9 u + 81 |
3 u |
Number of metallic bricks that Simon used for each house = 1 u
Number of metallic bricks that Xuan used for each house = 1 u + 9
Number of metallic bricks that Simon had
= 3 x 1 u
= 3 u
Number of metallic bricks that Xuan had
= 9 x (1 u + 9)
= 9 u + 81
Xuan had four times the number of metallic bricks as Simon.
4 x 3 u = 9 u + 81
12 u = 9 u + 81
12 u - 9 u = 81
3 u = 81
1 u = 81 ÷ 3 = 27
Number of bricks that Simon had
= 3 u
= 3 x 27
= 81
Answer(s): 81
