Before you add or subtract decimals, what must you do?
Steps to changing the power of 10 in SN:
Words that tell you to subtract:
1. Make sure that the decimal points are lined up.
2. If necessary, add zeros to the right of the last digit before the decimal point until both numbers have the same number of decimal places.
Words that tell you to subtract:
1. If the exponents of 10 are different, subtract the smaller exponent from the larger one to determine how many places you'll need to move the decimal point.