Question

Whats 4.25 increased by 15%

Answer 1

Two methods:
Method 1.
We are increasing, let us find 15% of 4.25
                                     =  15/100 *  4.25      5 into 15 and 100
                                     =    3/20 * 4.25          2 into 20 and 4.25    
                                     =     3/10 * 2.125
                                     =    3*2.125 / 10 =    6.375/10 = 0.6375

We add this answer to 4.25. 

0.6375 + 4.25 = 4.8875


Method 2:
Increasing by 15% :    (100 + 15) = 115%

We find 115% of 4.25

115 / 100 * 4.25 = 1.15 * 4.25 = 4.8875.   Use your calculator.

Answer 2

You would turn the 15% into a decimal which is .15 then multiply .15 by 4.25. After multiplying those together add 4.25 to the answer.