There are 3 pieces of ribbons with a total length of 5 m 92 cm. The first piece of ribbon is 38 cm more than the second piece of ribbon while the third piece is five times the length of the first piece of ribbon. Calculate the length of the third piece of ribbon. (Write the answer in metres and centimetres.)
Length of the first piece = 1 u
Length of the second piece = 1 u - 38
Length of the third piece = 5 u

Total length
= 1 u + 1 u - 38 + 5 u 
= 7 u - 38

Total length of 3 pieces of ribbons
= 5 m 92 cm
= 5 x 100 + 92
= 592 cm

7 u - 38 = 592 
7 u = 592 + 38 = 630
1 u = 630 ÷ 7 = 90 

Length of third piece of ribbon
= 5 u
= 5 x 90
= 450 cm

1 m = 100 cm
450 cm = 4 m 50 cm

Length of third piece of ribbon = 4 m 50 cm

Answer(s): 4 m 50 cm