Business Mathematics Brief 12th Edition by Stanley Salzman ,Gary Clendenen, Charles Miller

Exercise 270

Explain what happens when you round $.499 to the nearest dollar. ( See Objective. )
Round decimal numbers. It is important to be able to round decimals. For example, Walgreens sells two candy bars for $.79, but you want to buy only one candy bar. The price of one bar is $.79 ÷ 2, which is $.395, but you cannot pay part of a cent. So the store rounds the price up to $.40 for one bar. The steps to round decimal numbers are the same as those used to round whole numbers, which have already been discussed.

Rounding Decimals
Step 1 Find the place to which the number is to be rounded. Draw a vertical line after that place to show that you are cutting off the rest of the digits.
Step 2 Look at only the first digit to the right of your cut-off line. If the first digit is 5 or more, increase the digit in the place to which you are rounding by 1. Otherwise, do not change the digit in the place to which you are rounding.
Step 3 Drop all digits to the right of the place to which you have rounded.
To round 97.3892 to the nearest tenth, first draw a vertical line to the right of the 3 in the tenths place. The digit to the right of the vertical line is 5 or more, so round the 3 in the tenths position up to 4 and drop all digits to the right.

97.3892 rounded to the nearest tenth is 97.4.