PSLE Esther has a number of pencils in three colours: brown, blue and purple.
47 of the pencils are brown. The number of brown pencils is thrice the number of blue pencils. What fraction of the pencils is purple?
Brown |
Blue |
Purple |
Total |
4x3 |
3x3 |
7x3 |
3x4 |
1x4 |
|
|
12 u |
4 u |
5 u |
21 u |
Number of brown pencils is the repeated identity.
Make the number of brown pencils the same.
LCM of 4 and 3 = 12
Number of purple pencils
= 21 u - 12 u - 4 u
= 5 u
Fraction of the pencils that is purple
=
521 Answer(s):
521