A piece of ribbon 3100 cm long is cut into 3 parts, C, B and A.
C is 3 times as long as B.
A is 110 cm shorter than B.
Give the answers in cm.
- How much shorter is A than C?
- What is the total length of C and B?
(a)
Choose the shortest length to be 1 u.
Length of A = 1 u
Length of B = 1 u + 110
Length of C = 3 x (1 u + 110) = 3 u + 330
Total length of C, B and A
= 3 u + 330 + 1 u + 110 + 1 u
= 3 u + 1 u + 1 u + 330 + 110
= 5 u + 440
5 u + 440 = 3100
5 u = 3100 - 440
5 u = 2660
1 u = 2660 ÷ 5 = 532
Length of A shorter than C
= 3 u + 330 - 1 u
= 3 u - 1 u + 330
= 2 u + 330
= 2 x 532 + 330
= 1064 + 330
= 1394 cm
(b)
Total length of C and B = 3 u + 330 + 1 u + 110
= 3 u + 1 u + 330 + 110
= 4 x 532 + 440 = 2128 + 440 = 2568 cm Answer(s): (a) 1394 cm; (b) 2568 cm