A piece of ribbon 3600 cm long is cut into 3 parts, B, C and A.
B is 4 times as long as C.
A is 150 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 + 150
Length of B = 4 x (1 u + 150) = 4 u + 600
Total length of B, C and A
= 4 u + 600 + 1 u + 150 + 1 u
= 4 u + 1 u + 1 u + 600 + 150
= 6 u + 750
6 u + 750 = 3600
6 u = 3600 - 750
6 u = 2850
1 u = 2850 ÷ 6 = 475
Length of B longer than C
= 4 u + 600 - (1 u + 150)
= 4 u - 1 u + 600 - 150
= 3 u + 450
= 3 x 475 + 450
= 1425 + 450
= 1875 cm
(b)
Total length of B and A
= 4 u + 600 + 1 u
= 5 u + 600
= 5 x 475 + 600
= 2375 + 600
= 2975 cm
Answer(s): (a) 1875 cm; (b) 2975 cm