A bag contains 8 white and 12 black balls, the percentage of black balls in the bag is:

1. 20%

2. 150%

3. 60%

4. 40%

After paying 20% of the income, a man is left with ₹ 160; then the income of the man is:

1. ₹ 128

2. ₹ 192

3. ₹ 200

4. none of these

If A + B + C = 400 in which A is 40% and B is 45%, then the exact quantity of C in the whole is :

1. 160

2. 60

3. 180

4. 15%

A number is decreased by 20%. If the resulting number is 800, the original number is :

1. 640

2. 960

3. 1000

4. 600