A piece of ribbon 1900 cm long is cut into 3 parts, A, C and B.
A is 3 times as long as C.
B is 230 cm shorter than C.
Give the answers in cm.
- How much shorter is B than A?
- What is the total length of A and C?
(a)
Choose the shortest length to be 1 u.
Length of B = 1 u
Length of C = 1 u + 230
Length of A = 3 x (1 u + 230) = 3 u + 690
Total length of A, C and B
= 3 u + 690 + 1 u + 230 + 1 u
= 3 u + 1 u + 1 u + 690 + 230
= 5 u + 920
5 u + 920 = 1900
5 u = 1900 - 920
5 u = 980
1 u = 980 ÷ 5 = 196
Length of B shorter than A
= 3 u + 690 - 1 u
= 3 u - 1 u + 690
= 2 u + 690
= 2 x 196 + 690
= 392 + 690
= 1082 cm
(b)
Total length of A and C = 3 u + 690 + 1 u + 230
= 3 u + 1 u + 690 + 230
= 4 x 196 + 920 = 784 + 920 = 1704 cm Answer(s): (a) 1082 cm; (b) 1704 cm
