A piece of ribbon 1300 cm long is cut into 3 parts, B, C and A.
B is 3 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 = 3 x (1 u + 260) = 3 u + 780
Total length of B, C and A
= 3 u + 780 + 1 u + 260 + 1 u
= 3 u + 1 u + 1 u + 780 + 260
= 5 u + 1040
5 u + 1040 = 1300
5 u = 1300 - 1040
5 u = 260
1 u = 260 ÷ 5 = 52
Length of A shorter than B
= 3 u + 780 - 1 u
= 3 u - 1 u + 780
= 2 u + 780
= 2 x 52 + 780
= 104 + 780
= 884 cm
(b)
Total length of B and C = 3 u + 780 + 1 u + 260
= 3 u + 1 u + 780 + 260
= 4 x 52 + 1040 = 208 + 1040 = 1248 cm Answer(s): (a) 884 cm; (b) 1248 cm