Cathy had twice the number of plastic bricks as Julian. Cathy used all her bricks to build 8 identical planes. Julian used all his bricks to build 6 identical planes. Cathy used 9 more bricks than Julian for each plane. How many bricks did Julian have?
| |
Cathy |
Julian |
| Number |
8 |
6 |
| Value |
1 u + 9 |
1 u |
| Total value |
8 u + 72 |
6 u |
Number of plastic bricks that Julian used for each plane = 1 u
Number of plastic bricks that Cathy used for each plane = 1 u + 9
Number of plastic bricks that Julian had
= 6 x 1 u
= 6 u
Number of plastic bricks that Cathy had
= 8 x (1 u + 9)
= 8 u + 72
Cathy had twice the number of plastic bricks as Julian.
2 x 6 u = 8 u + 72
12 u = 8 u + 72
12 u - 8 u = 72
4 u = 72
1 u = 72 ÷ 4 = 18
Number of bricks that Julian had
= 6 u
= 6 x 18
= 108
Answer(s): 108
