PSLE
Winnie had two streamers of the same length. She cut the first streamer into equal parts of length 30 cm and to each part she tied 2 purple balls. After that, she cut the second streamer into equal parts of length 45 cm and to each part she tied 5 red balls. When she finished tying, she counted that there were 16 more red balls than purple balls. How many balls were there altogether?

	First streamer	Second streamer	Difference	Total
Length of each part	30 cm	45 cm
Number of balloons tied to each part	2 purple balloons	5 red balloons
LCM	90 cm	90 cm
Number of equal parts	90 ÷ 30 = 3	90 ÷ 45 = 2
Number of balloons for each streamer per set	3 x 2 = 6	5 x 2 = 10	10 - 6 = 4	6 + 10 = 16

LCM of 30 and 45 = 90

Number of sets of 2 purple balls in a length of 90 cm
= 90 ÷ 30
= 3

Number of purple balls in a length of 90 cm
= 3 x 2
= 6

Number of sets of 5 red balls in a length of 90 cm
= 90 ÷ 45
= 2

Number of red balls in a length of 90 cm
= 2 x 5
= 10

Extra number of red balls in a length of 90 cm
= 10 - 6
= 4

Number of sets of balls
= 16 ÷ 4
= 4

Total number of balls in one set of 90 cm of purple balloons and one set of 90 cm of red balloons
= 6 + 10
= 16

Total number of balls of the two streamers
= 4 x 16
= 64

Answer(s): 64