6% is simply 6/100
Multiply 6/100 by 131/1.
You get 786/100. Now, reduce and you have your answer.
When dividing by 10, 100, 1000 ... etc
You move the decimal place by the number of zeros.
786. -- In your case we need to move the decimal point to the left because were dividing (you move it to the right, when multiplying)
So when dividing by 100 we would move the decimal place over to the left 2 times.
7.86
If we divided by 10
78.6
by 1000
0.786
by 10,000
0.0786 -- If we multiply 0.0786 by 100,000 the decimal place moves to the right 5 times
7860. or just 7860
Hope this helps.