Question

A box has 100 blue balls,50 red balls and 50 black balls,25% of blue balls and 50% of red balls are taken away.Then,percentage of black balls at present is

Answer 1

1. In blue balls =25%of blue ball

=25/100×100

=25

25 ball is taken

=100-25

=75 balls remain

2. In red ball=50%of red balls

=50%×50

=25balls remain

percentage of black ball=total no. of ball÷no.of black ball

=(200-75-25)÷50

=100÷50

=2%

black ball is 2%