Question

On a sports day, a school bought 1,500 color paper bundles in which 20 % were green colored, 30% were white colored and remaining were blue colored. Number of blue colored bundles is
  (A) 1000
  (B) 500
  (C) 700
  (D) 750

Answer 1

Hint-It can be solved by calculating the number of bundles of green and white color. After calculating, we will delete the number of white and green colored bundles from 1500 to get the remaining blue colored bundles. The percentage for white and green colored bundles is given in the question.
Complete step-by-step solution -
The percentage for white and green colored bundles is given in the question.
Percentage of green colored bundles = 20%
Number of green colored bundles $ \Rightarrow (20 * 1500)/100 = 300{\text{ green bundles}}$
Percentage of white colored bundles =30%
Number of white colored bundles $ \Rightarrow (30 * 1500)/100 = 450{\text{ white bundles}}$
Number of white and green colored bundles is
$ \Rightarrow 300 + 450 = 750$
Remaining number of bundles will be blue colored and is equal to
$ \Rightarrow 1500 - 750 = 750{\text{ blue bundles}}$ .
$\therefore {\text{ Number of blue colored bundles is 750}}$
So, D is the correct option.

Note-These type of question can also be solved by directly calculating the percentage of blue colored bundles. Now, the percentage for blue colored bundles is obtained by subtracting the percentage of white and green colored bundles from 100.The percentage for white and green colored bundles is given in the question.