44
Section 1 Whole Numbers
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Step 2: Subtract the amount taken by another job
348″
− 24″
‾
324″
Step 3: Divide the weight per foot by the number of inches in a foot (12) to fi nd
the weight per inch in ounces.
4
12
|
–––
48
– 48
‾
00
Step 4: Multiply the weight per inch by the number of inches of bar stock.
324
× 4
‾
1,296 ounces
Step 5: Divide the total number of ounces (1,296) by the number of ounces in a
pound (16) to fi nd the number of pounds.
81
16
|
–––––
1296
– 128
‾
16
– 16
‾
00
Step 6: Multiply the number of pounds of bar stock (81) by the cost per foot ($3)
to fi nd the total cost.
81
× 3
‾
243 dollars
The order in which you do the math operations can be very important. It is not
possible to specify one order of operations to cover all math problems. Every prob-
lem must be considered on its own. It is generally helpful to write down all of the
relevant facts in the problem before you do anything else. Then write the problem
with the steps in the order they need to be taken. The acronym PEMDAS is helpful
in determining the order in which operations should be performed. The letters in
PEMDAS represent the following:
P Parentheses (Do the operations in parentheses fi rst.)
E Exponents (Powers and roots of numbers. These are explained in a later unit.)
MD Multiplication and Division (Do multiplication and division from left to right.)
AS Addition and Subtraction (Do addition and subtraction from left to right.)