The answer to this is 59. 10 x 5.9 = 59
The easiest way to do this is to understand what happens to the decimal point when you multiply a number by 10 (or by 100 or by any multiple of 10). When you multiply by 10, all you have to do is to move the decimal point over one place to the right. When you do that, 5.9 becomes 59.
A similar thing happens when you multiply by other multiples of 10. If you multiply by 100, for example, you move the decimal point over two places to the right -- one place for each zero in the multiple of 10.
Answer to multiplication of any decimal number multiplied by 10 can be obtained by shifting the decimal point one place to the right.
Thus to multiply 5.9 by 10 we move the decimal place between 5 and 9 to the position just after 9. This gives us the answer 59.
Please note that in a number when there is digit other than 0 in places to the right after the decimal place, the decimal point may not be shown. Thus all numbers like 59.0, 59.00, 59.000 and so on have the same value and may be written without the decimal point as 59.