A piece of ribbon 3300 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 longer is B than C?
- What is the total length of B and A?
(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 = 3300
5 u = 3300 - 1040
5 u = 2260
1 u = 2260 ÷ 5 = 452
Length of B longer than C
= 3 u + 780 - (1 u + 260)
= 3 u - 1 u + 780 - 260
= 2 u + 520
= 2 x 452 + 520
= 904 + 520
= 1424 cm
(b)
Total length of B and A
= 3 u + 780 + 1 u
= 4 u + 780
= 4 x 452 + 780
= 1808 + 780
= 2588 cm
Answer(s): (a) 1424 cm; (b) 2588 cm