Find the value of 31.2 -12.125 with due consideration of significant figures.

Explanation

31.2 -12.125
Here 31.2 has one decimal place, hence 12.125 is to be rounded off to 1+1 = 2 decimal places 12.125 is rounded off as 12.12
`therefore 31.2 - 12.12 = 19.08`
finally we should have only one decimal place and hence 19.08 is to be rounded off as 19.1 .