A piece of ribbon 4300 cm long is cut into 3 parts, C, A and B.
C is 3 times as long as A.
B is 160 cm shorter than A.
Give the answers in cm.
- How much shorter is B than C?
- What is the total length of C and A?
(a)
Choose the shortest length to be 1 u.
Length of B = 1 u
Length of A = 1 u + 160
Length of C = 3 x (1 u + 160) = 3 u + 480
Total length of C, A and B
= 3 u + 480 + 1 u + 160 + 1 u
= 3 u + 1 u + 1 u + 480 + 160
= 5 u + 640
5 u + 640 = 4300
5 u = 4300 - 640
5 u = 3660
1 u = 3660 ÷ 5 = 732
Length of B shorter than C
= 3 u + 480 - 1 u
= 3 u - 1 u + 480
= 2 u + 480
= 2 x 732 + 480
= 1464 + 480
= 1944 cm
(b)
Total length of C and A = 3 u + 480 + 1 u + 160
= 3 u + 1 u + 480 + 160
= 4 x 732 + 640 = 2928 + 640 = 3568 cm Answer(s): (a) 1944 cm; (b) 3568 cm