A piece of ribbon 3200 cm long is cut into 3 parts, C, B and A.
C is 3 times as long as B.
A is 220 cm shorter than B.
Give the answers in cm.
- How much shorter is A than C?
- What is the total length of C and B?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of B = 1 u + 220
Length of C = 3 x (1 u + 220) = 3 u + 660
Total length of C, B and A
= 3 u + 660 + 1 u + 220 + 1 u
= 3 u + 1 u + 1 u + 660 + 220
= 5 u + 880
5 u + 880 = 3200
5 u = 3200 - 880
5 u = 2320
1 u = 2320 ÷ 5 = 464
Length of A shorter than C
= 3 u + 660 - 1 u
= 3 u - 1 u + 660
= 2 u + 660
= 2 x 464 + 660
= 928 + 660
= 1588 cm
(b)
Total length of C and B = 3 u + 660 + 1 u + 220
= 3 u + 1 u + 660 + 220
= 4 x 464 + 880 = 1856 + 880 = 2736 cm Answer(s): (a) 1588 cm; (b) 2736 cm