Lucy had thrice the number of rubber bricks as Tom. Lucy used all her bricks to build 12 identical figurines. Tom used all his bricks to build 5 identical figurines. Lucy used 9 more bricks than Tom for each figurine. How many bricks did Tom have?

	Lucy	Tom
Number	12	5
Value	1 u + 9	1 u
Total value	12 u + 108	5 u

Number of rubber bricks that Tom used for each figurine = 1 u
Number of rubber bricks that Lucy used for each figurine = 1 u + 9

Number of rubber bricks that Tom had
= 5 x 1 u
= 5 u

Number of rubber bricks that Lucy had
= 12 x (1 u + 9)
= 12 u + 108

Lucy had thrice the number of rubber bricks as Tom.

3 x 5 u = 12 u + 108
15 u = 12 u + 108
15 u - 12 u = 108
3 u = 108

1 u = 108 ÷ 3 = 36

Number of bricks that Tom had
= 5 u
= 5 x 36
= 180

Answer(s): 180