Yen had two rolls of ribbons of the same length but different designs. She cut the first roll of ribbon into equal pieces of length 48 cm and there were 4 squares on each piece of ribbon and cut the second roll of ribbon into equal pieces of length 80 cm and there were 7 triangles on each piece of ribbon as shown. After she finished cutting both rolls of ribbons, she counted that the total number of triangles was 22 more than the total number of squares. Find the length of one roll of ribbon in cm.
To make the lengths of the two rolls of ribbons were the same, find the LCM of 48 and 80.

LCM of 48 and 80 = 240

Number of sets of 48 cm in a length of 240 cm
= 240 ÷ 48
= 5

Number of sets of 80 cm in a length of 240 cm
= 240 ÷ 80
= 3

Number of squares in a length of 240 cm
= 5 x 4
= 20

Number of triangles in a length of 240 cm
= 3 x 7
= 21

Number of more triangles than squares in 1 set of 240 cm length
= 21 - 20
= 1

Number of sets of 1 more triangles than squares
= 22 ÷ 1
= 22

Length of one roll of ribbon
= 22 x 240
= 5280 cm

Answer(s): 5280 cm