What is 3.14 x 4?

Answer 1

Don't get cared by the decimal, it's just a point. It means: divide by 10^n where n is the number of digits after the decimal.

So in this case, 3.14 means 314 / 10^2 = 314 / 100

so you are actually doing this 314/100 x 4 = 314 x 1/100 x 4. Multiplication is commutative so you might as well do 4 x 314, then divide by 100.

So you should get 1256 / 100. To divide by 100, recall what decimal means, it's simply 12.56 :D

Answer 2

12.56