The gre anlytycal writting section 5 ppt

Operations with Decimals

To add and subtract decimals, you must always remember to line up the decimal points:

356.7 3.456 8.9347

+ 34.9854 + .333 – 0.24

391.6854 3.789 8.6947

To multiply decimals, it is not necessary to align decimal points. Simply perform the multiplication as if there

were no decimal point. Then, to determine the placement of the decimal point in the answer, count the numbers

located to the right of the decimal point in the decimals being multiplied. The total numbers to the right of the

decimal point in the original problem is the number of places the decimal point is moved in the product.

For example:

To divide a decimal by another, such as 13.916

2.45 or 2.4513.916, move the decimal point in the

divisor to the right until the divisor becomes a whole number. Next, move the decimal point in the dividend

the same number of places:

This process results in the correct position of the decimal point in the quotient. The problem can now be

solved by performing simple long division:

Percents

A percent is a measure of a part to a whole, with the whole being equal to 100.

■ To change a decimal to a percentage, move the decimal point two units to the right and add a percent￾age symbol.

245 1391.6

5.68

–1225

166 6

–1470

1960

245 1391.6

1 2.3 4

2 2

x .5 62 1

4 3

7 4 0 4

6 1 7 0 0

6.9 1 0 4 4 3 2 1

= TOTAL #'s TO THE RIGHT OF

THE DECIMAL POINT = 4

–THE GRE QUANTITATIVE SECTION–

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