A piece of ribbon 2300 cm long is cut into 3 parts, B, C and A.
B is 4 times as long as C.
A is 130 cm shorter than C.
Give the answers in cm.
- How much longer is B than C?
- What is the total length of B and A?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of C = 1 u + 130
Length of B = 4 x (1 u + 130) = 4 u + 520
Total length of B, C and A
= 4 u + 520 + 1 u + 130 + 1 u
= 4 u + 1 u + 1 u + 520 + 130
= 6 u + 650
6 u + 650 = 2300
6 u = 2300 - 650
6 u = 1650
1 u = 1650 ÷ 6 = 275
Length of B longer than C
= 4 u + 520 - (1 u + 130)
= 4 u - 1 u + 520 - 130
= 3 u + 390
= 3 x 275 + 390
= 825 + 390
= 1215 cm
(b)
Total length of B and A
= 4 u + 520 + 1 u
= 5 u + 520
= 5 x 275 + 520
= 1375 + 520
= 1895 cm
Answer(s): (a) 1215 cm; (b) 1895 cm