Arithmetic Reasoning
Decimals
Yesterday I presented a question on multiplication with decimals
What is .40 x .90?
In working as an ASVAB tutor, I remind my students of the importance of knowing how to work with decimals. Examples with decimals could appear on the Arithmetic Reasoning section of the Mathematics Knowledge section of the ASVAB. In multiplying with decimals, it is not necessary to line up the decimals when multiplying them.
.40 has 2 digits after the decimal place.
.90 has 2 digits after the decimal place.
Since each number has 2 digits after the decimal place, that is a total of 4 digits after the decimal place.
The numbers are multiplied by each other, and the decimal is moved 4 places to the left.
.40 x .90 = .3600 = .36
The 2 zeroes are not necessary so .3600 can be written as .36.
