Question

Isabella had a big bag of sweets,she ate two fifth of them on Monday,two fifth of those remaining on Tuesday,and two thirds of what remaining on Wednesday.She then had 12 sweets.How many were in the bag originally?

Answer 1

100 sweets

Explanation:

Let initial number of sweet = x

Monday :

2/5 of x = 2x/5

Number left = x - 2x/5 = 3x/5

Tuesday :

2/5 of remaining = 2/5 * 3x/5 = 6x/25

Number left = 3x/5 - 6/25 = 9x/25

Wednesday :

2/3 of remaining = 2/3 * 9x/25 = 18x/75

Number left = 9x/25 - 18x/75 = 9x / 75

9x/75 corresponds to 12

9x/75 = 12

Cross multiply :

9x = 12 * 75

9x = 900

x = 900 / 9

x = 100 sweets