A piece of ribbon 4500 cm long is cut into 3 parts, B, C and A.
B is 2 times as long as C.
A is 220 cm shorter than C.
Give the answers in cm.
- How much shorter is A than B?
- What is the total length of B and C?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of C = 1 u + 220
Length of B = 2 x (1 u + 220) = 2 u + 440
Total length of B, C and A
= 2 u + 440 + 1 u + 220 + 1 u
= 2 u + 1 u + 1 u + 440 + 220
= 4 u + 660
4 u + 660 = 4500
4 u = 4500 - 660
4 u = 3840
1 u = 3840 ÷ 4 = 960
Length of A shorter than B
= 2 u + 440 - 1 u
= 2 u - 1 u + 440
= 1 u + 440
= 1 x 960 + 440
= 960 + 440
= 1400 cm
(b)
Total length of B and C = 2 u + 440 + 1 u + 220
= 2 u + 1 u + 440 + 220
= 3 x 960 + 660 = 2880 + 660 = 3540 cm Answer(s): (a) 1400 cm; (b) 3540 cm