A piece of ribbon 4500 cm long is cut into 3 parts, C, B and A.
C is 3 times as long as B.
A is 250 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 + 250
Length of C = 3 x (1 u + 250) = 3 u + 750
Total length of C, B and A
= 3 u + 750 + 1 u + 250 + 1 u
= 3 u + 1 u + 1 u + 750 + 250
= 5 u + 1000
5 u + 1000 = 4500
5 u = 4500 - 1000
5 u = 3500
1 u = 3500 ÷ 5 = 700
Length of A shorter than C
= 3 u + 750 - 1 u
= 3 u - 1 u + 750
= 2 u + 750
= 2 x 700 + 750
= 1400 + 750
= 2150 cm
(b)
Total length of C and B = 3 u + 750 + 1 u + 250
= 3 u + 1 u + 750 + 250
= 4 x 700 + 1000 = 2800 + 1000 = 3800 cm Answer(s): (a) 2150 cm; (b) 3800 cm