Kevin, one of the GMAT experts at Magoosh covers a useful GMAT Maths strategy for multiplying that will save you time and energy on the test day. We all know that we don't get a calculator on the maths section of the GMAT, so we really have to understand what we are doing when we multiply to make it easier.
Learn simple it is to use halving and doubling. See how it works and how you can multiply 150 by 36 in just seconds.