A piece of ribbon 3300 cm long is cut into 3 parts, B, C and A.
B is 4 times as long as C.
A is 210 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 + 210
Length of B = 4 x (1 u + 210) = 4 u + 840
Total length of B, C and A
= 4 u + 840 + 1 u + 210 + 1 u
= 4 u + 1 u + 1 u + 840 + 210
= 6 u + 1050
6 u + 1050 = 3300
6 u = 3300 - 1050
6 u = 2250
1 u = 2250 ÷ 6 = 375
Length of B longer than C
= 4 u + 840 - (1 u + 210)
= 4 u - 1 u + 840 - 210
= 3 u + 630
= 3 x 375 + 630
= 1125 + 630
= 1755 cm
(b)
Total length of B and A
= 4 u + 840 + 1 u
= 5 u + 840
= 5 x 375 + 840
= 1875 + 840
= 2715 cm
Answer(s): (a) 1755 cm; (b) 2715 cm