Cracking The SAT Premium

2. =

3. 3.72 ÷ 0.02 =

4. 0.71 – 3.6 =

Comparing Decimals

Some SAT problems will ask you to determine whether one decimal is larger or smaller than another.
Many students have trouble doing this. It isn’t difficult, though, and you will do fine as long as you
remember to line up the decimal points and fill in missing zeros.

Place   Value

Compare decimals

place   by  place,  going

from    left    to  right.

Here’s an example:

Problem: Which is larger, 0.0099 or 0.01?

Solution: Simply place one decimal over the other with the decimal points lined up, like this:

0.0099

0.01

To make the solution seem clearer, you can add two zeros to the right of 0.01. (You can always add zeros
to the right of a decimal without changing its value.) Now you have this:

0.0099

0.0100

Which decimal is larger? Clearly, 0.0100 is, just as 100 is larger than 99. Remember that 0.0099 =

,   while   0.0100  =   .

Analysis

Watch out for problems like this with decimals in the answers. Any time you encounter a problem
involving the comparison of decimals, be sure to stop and ask yourself whether you are about to make a
careless mistake.

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