Zara had five times the number of plastic bricks as Carl. Zara used all her bricks to build 10 identical houses. Carl used all his bricks to build 3 identical houses. Zara used 9 more bricks than Carl for each house. How many bricks did Carl have?
| |
Zara |
Carl |
| Number |
10 |
3 |
| Value |
1 u + 9 |
1 u |
| Total value |
10 u + 90 |
3 u |
Number of plastic bricks that Carl used for each house = 1 u
Number of plastic bricks that Zara used for each house = 1 u + 9
Number of plastic bricks that Carl had
= 3 x 1 u
= 3 u
Number of plastic bricks that Zara had
= 10 x (1 u + 9)
= 10 u + 90
Zara had five times the number of plastic bricks as Carl.
5 x 3 u = 10 u + 90
15 u = 10 u + 90
15 u - 10 u = 90
5 u = 90
1 u = 90 ÷ 5 = 18
Number of bricks that Carl had
= 3 u
= 3 x 18
= 54
Answer(s): 54
