A piece of ribbon 3700 cm long is cut into 3 parts, B, C and A.
B is 4 times as long as C.
A is 260 cm shorter than C.
Give the answers in cm.
- How much shorter is A than B?
- What is the total length of B and C?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of C = 1 u + 260
Length of B = 4 x (1 u + 260) = 4 u + 1040
Total length of B, C and A
= 4 u + 1040 + 1 u + 260 + 1 u
= 4 u + 1 u + 1 u + 1040 + 260
= 6 u + 1300
6 u + 1300 = 3700
6 u = 3700 - 1300
6 u = 2400
1 u = 2400 ÷ 6 = 400
Length of A shorter than B
= 4 u + 1040 - 1 u
= 4 u - 1 u + 1040
= 3 u + 1040
= 3 x 400 + 1040
= 1200 + 1040
= 2240 cm
(b)
Total length of B and C = 4 u + 1040 + 1 u + 260
= 4 u + 1 u + 1040 + 260
= 5 x 400 + 1300 = 2000 + 1300 = 3300 cm Answer(s): (a) 2240 cm; (b) 3300 cm