A piece of ribbon 2700 cm long is cut into 3 parts, B, C and A.
B is 4 times as long as C.
A is 240 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 + 240
Length of B = 4 x (1 u + 240) = 4 u + 960
Total length of B, C and A
= 4 u + 960 + 1 u + 240 + 1 u
= 4 u + 1 u + 1 u + 960 + 240
= 6 u + 1200
6 u + 1200 = 2700
6 u = 2700 - 1200
6 u = 1500
1 u = 1500 ÷ 6 = 250
Length of A shorter than B
= 4 u + 960 - 1 u
= 4 u - 1 u + 960
= 3 u + 960
= 3 x 250 + 960
= 750 + 960
= 1710 cm
(b)
Total length of B and C = 4 u + 960 + 1 u + 240
= 4 u + 1 u + 960 + 240
= 5 x 250 + 1200 = 1250 + 1200 = 2450 cm Answer(s): (a) 1710 cm; (b) 2450 cm