A piece of ribbon 1100 cm long is cut into 3 parts, B, A and C.
B is 4 times as long as A.
C is 130 cm shorter than A.
Give the answers in cm.
- How much longer is B than A?
- What is the total length of B and C?
(a)
Choose the shortest length to be 1 u.
Length of C = 1 u
Length of A = 1 u + 130
Length of B = 4 x (1 u + 130) = 4 u + 520
Total length of B, A and C
= 4 u + 520 + 1 u + 130 + 1 u
= 4 u + 1 u + 1 u + 520 + 130
= 6 u + 650
6 u + 650 = 1100
6 u = 1100 - 650
6 u = 450
1 u = 450 ÷ 6 = 75
Length of B longer than A
= 4 u + 520 - (1 u + 130)
= 4 u - 1 u + 520 - 130
= 3 u + 390
= 3 x 75 + 390
= 225 + 390
= 615 cm
(b)
Total length of B and C
= 4 u + 520 + 1 u
= 5 u + 520
= 5 x 75 + 520
= 375 + 520
= 895 cm
Answer(s): (a) 615 cm; (b) 895 cm