PSLE
Tiffany had two ribbons of the same length. She cut the first ribbon into equal parts of length 20 cm and to each part she tied 2 brown paper cranes. After that, she cut the second ribbon into equal parts of length 25 cm and to each part she tied 3 green paper cranes. When she finished tying, she counted that there were 6 more green paper cranes than brown paper cranes. How many paper cranes were there altogether?

	First ribbon	Second ribbon	Difference	Total
Length of each part	20 cm	25 cm
Number of balloons tied to each part	2 brown balloons	3 green balloons
LCM	100 cm	100 cm
Number of equal parts	100 ÷ 20 = 5	100 ÷ 25 = 4
Number of balloons for each ribbon per set	5 x 2 = 10	3 x 4 = 12	12 - 10 = 2	10 + 12 = 22

LCM of 20 and 25 = 100

Number of sets of 2 brown paper cranes in a length of 100 cm
= 100 ÷ 20
= 5

Number of brown paper cranes in a length of 100 cm
= 5 x 2
= 10

Number of sets of 3 green paper cranes in a length of 100 cm
= 100 ÷ 25
= 4

Number of green paper cranes in a length of 100 cm
= 4 x 3
= 12

Extra number of green paper cranes in a length of 100 cm
= 12 - 10
= 2

Number of sets of paper cranes
= 6 ÷ 2
= 3

Total number of paper cranes in one set of 100 cm of brown balloons and one set of 100 cm of green balloons
= 10 + 12
= 22

Total number of paper cranes of the two ribbons
= 3 x 22
= 66

Answer(s): 66