PSLE
Cindy had two ribbons of the same length. She cut the first ribbon into equal parts of length 25 cm and to each part she tied 2 black paper cranes. After that, she cut the second ribbon into equal parts of length 30 cm and to each part she tied 3 pink paper cranes. When she finished tying, she counted that there were 12 more pink paper cranes than black paper cranes. How many paper cranes were there altogether?

	First ribbon	Second ribbon	Difference	Total
Length of each part	25 cm	30 cm
Number of balloons tied to each part	2 black balloons	3 pink balloons
LCM	150 cm	150 cm
Number of equal parts	150 ÷ 25 = 6	150 ÷ 30 = 5
Number of balloons for each ribbon per set	6 x 2 = 12	3 x 5 = 15	15 - 12 = 3	12 + 15 = 27

LCM of 25 and 30 = 150

Number of sets of 2 black paper cranes in a length of 150 cm
= 150 ÷ 25
= 6

Number of black paper cranes in a length of 150 cm
= 6 x 2
= 12

Number of sets of 3 pink paper cranes in a length of 150 cm
= 150 ÷ 30
= 5

Number of pink paper cranes in a length of 150 cm
= 5 x 3
= 15

Extra number of pink paper cranes in a length of 150 cm
= 15 - 12
= 3

Number of sets of paper cranes
= 12 ÷ 3
= 4

Total number of paper cranes in one set of 150 cm of black balloons and one set of 150 cm of pink balloons
= 12 + 15
= 27

Total number of paper cranes of the two ribbons
= 4 x 27
= 108

Answer(s): 108