A piece of ribbon 1700 cm long is cut into 3 parts, C, A and B.
C is 2 times as long as A.
B is 140 cm shorter than A.
Give the answers in cm.
- How much shorter is B than C?
- What is the total length of C and A?
(a)
Choose the shortest length to be 1 u.
Length of B = 1 u
Length of A = 1 u + 140
Length of C = 2 x (1 u + 140) = 2 u + 280
Total length of C, A and B
= 2 u + 280 + 1 u + 140 + 1 u
= 2 u + 1 u + 1 u + 280 + 140
= 4 u + 420
4 u + 420 = 1700
4 u = 1700 - 420
4 u = 1280
1 u = 1280 ÷ 4 = 320
Length of B shorter than C
= 2 u + 280 - 1 u
= 2 u - 1 u + 280
= 1 u + 280
= 1 x 320 + 280
= 320 + 280
= 600 cm
(b)
Total length of C and A = 2 u + 280 + 1 u + 140
= 2 u + 1 u + 280 + 140
= 3 x 320 + 420 = 960 + 420 = 1380 cm Answer(s): (a) 600 cm; (b) 1380 cm