A piece of ribbon 1700 cm long is cut into 3 parts, C, A and B.
C is 3 times as long as A.
B is 130 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 + 130
Length of C = 3 x (1 u + 130) = 3 u + 390
Total length of C, A and B
= 3 u + 390 + 1 u + 130 + 1 u
= 3 u + 1 u + 1 u + 390 + 130
= 5 u + 520
5 u + 520 = 1700
5 u = 1700 - 520
5 u = 1180
1 u = 1180 ÷ 5 = 236
Length of B shorter than C
= 3 u + 390 - 1 u
= 3 u - 1 u + 390
= 2 u + 390
= 2 x 236 + 390
= 472 + 390
= 862 cm
(b)
Total length of C and A = 3 u + 390 + 1 u + 130
= 3 u + 1 u + 390 + 130
= 4 x 236 + 520 = 944 + 520 = 1464 cm Answer(s): (a) 862 cm; (b) 1464 cm