A piece of ribbon 1100 cm long is cut into 3 parts, B, C and A.
B is 3 times as long as C.
A is 190 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 + 190
Length of B = 3 x (1 u + 190) = 3 u + 570
Total length of B, C and A
= 3 u + 570 + 1 u + 190 + 1 u
= 3 u + 1 u + 1 u + 570 + 190
= 5 u + 760
5 u + 760 = 1100
5 u = 1100 - 760
5 u = 340
1 u = 340 ÷ 5 = 68
Length of A shorter than B
= 3 u + 570 - 1 u
= 3 u - 1 u + 570
= 2 u + 570
= 2 x 68 + 570
= 136 + 570
= 706 cm
(b)
Total length of B and C = 3 u + 570 + 1 u + 190
= 3 u + 1 u + 570 + 190
= 4 x 68 + 760 = 272 + 760 = 1032 cm Answer(s): (a) 706 cm; (b) 1032 cm