A piece of ribbon 4300 cm long is cut into 3 parts, C, B and A.
C is 4 times as long as B.
A is 140 cm shorter than B.
Give the answers in cm.
- How much longer is C than B?
- What is the total length of C and A?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of B = 1 u + 140
Length of C = 4 x (1 u + 140) = 4 u + 560
Total length of C, B and A
= 4 u + 560 + 1 u + 140 + 1 u
= 4 u + 1 u + 1 u + 560 + 140
= 6 u + 700
6 u + 700 = 4300
6 u = 4300 - 700
6 u = 3600
1 u = 3600 ÷ 6 = 600
Length of C longer than B
= 4 u + 560 - (1 u + 140)
= 4 u - 1 u + 560 - 140
= 3 u + 420
= 3 x 600 + 420
= 1800 + 420
= 2220 cm
(b)
Total length of C and A
= 4 u + 560 + 1 u
= 5 u + 560
= 5 x 600 + 560
= 3000 + 560
= 3560 cm
Answer(s): (a) 2220 cm; (b) 3560 cm