The length of a wooden block is 3 m 2 cm long. Betty cut the wooden block into 3 pieces. The length of the first piece of the wooden block is 38 cm. The length of the second piece of the wooden block is 2 m shorter than the third piece. What is the length of the third piece of wooden block?
1 m = 100 cm

Difference in the length between the second and the third piece
= 2 m
= 2 x 100
= 200 cm

Length of a wooden block
= 3 m 2 cm
= 3 x 100 + 2
= 302 cm

Length of the first piece = 38 cm
Length of the second piece = 1 u
Length of the third piece = 1 u + 200 cm

1 u + 1 u + 200 + 38 = 302
2 u + 238 = 302
2 u = 302 - 238 = 64
1 u = 64 ÷ 2 = 32 

Length of the third piece of wooden block
= 1 u + 200
= 32 + 200
= 232 cm

Answer(s): 232 cm