8.find the result when 40 is increased by 85%
10.find the result when 350 is decreased by 10%
28.find the result when 24 is increased by 75%
30.find the result when 30 is decreased by 85%

Q8. The answer is 74.

Let 40 be 100%.

Step 1. Calculate 85% of 40.
If 40 is 100%, how much will be 85%:
40 : 100% = x : 85%
x * 100% = 40 * 85%
x = 40 * 85% / 100% = 34

Step 2: Add given value to 40 (since it is increased):
40 + 34 = 74

Q10. The answer is 315.

Let 350 be 100%.

Step 1. Calculate 10% of 350.
If 350 is 100%, how much will be 10%:
350 : 100% = x : 10%
x * 100% = 350 * 10%
x = 350 * 10% / 100% = 35

Step 2: Distract given value from 350 (since it is decreased):
350 - 35 = 315

Q28. The answer is 42.

Let 24 be 100%.

Step 1. Calculate 75% of 24.
If 24 is 100%, how much will be 75%:
24 : 100% = x : 75%
x * 100% = 24 * 75%
x = 24 * 75% / 100% = 18

Step 2: Add given value to 24 (since it is increased):
24 + 18 = 42

Q10. The answer is 4.5.

Let 30 be 100%.

Step 1. Calculate 85% of 30.
If 30 is 100%, how much will be 85%:
30 : 100% = x : 85%
x * 100% = 30 * 85%
x = 30 * 85% / 100% = 25.5

Step 2: Distract given value from 30 (since it is decreased):
30 - 25.5 = 4.5