Tip 1: When you add or subtract decimals, you have to align your place values (align the decimal point).
Tip 2: An easy way to multiply a decimal number by powers of 10 (10, 100, 1,000, etc) is to simply move the decimal point to the right the same number of times as there are zeros. For example, try multiplying 0.03 × 10,000. How many zeros are there in 10,000? There are 4 – so move the decimal point in 0.03 to the right 4 places, giving you 300.