| Algebra I Recipe: Numbers and Number Operations |
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A. Definitions
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whole numbers - are positive numbers beginning with zero such as 0, 1, 2, 3, 4, . . .
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fraction - is a part of a whole number written with a fraction bar where the top number is the numerator and the bottom number is the denominator.
- Given the fraction 3/5, 3 is the numerator and 5 is the denominator.
- To change a fraction to a decimal, divide the denominator into the numerator.
for example: ½ = 1 ÷ 2 = 0.5
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decimal - is a part of a whole number written with a decimal point where the place values to the right of the decimal are: . (tenths) (hundredths) (thousandths) (ten thousandths) etc.
- To round a number to a particular place value, look at the number to the immediate right of the place value and if it is 5 or more round up one, but if it is 4 or less leave at the same value.
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- To change a decimal to a percent, move the decimal two places to the right.
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percent - some part out of 100.
- To change a percent to a fraction, put the number over 100 and then reduce.
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- To change a percent to a decimal, move the decimal two places left.
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numerical expression - an expression with numbers and operations such as [8 - 3(2)] ÷ 6
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grouping symbols
- parentheses ( )
- brackets [ ]
- braces { }
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evaluate - means to find the value of the expression.
- Perform operations inside parentheses.
- Perform all multiplication and division as they appear from left to right.
- Perform all addition and subtraction as they appear from left to right.
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perimeter - is the distance around an object.
- Find the perimeter by adding the lengths of each side of the object together.
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area of a rectangle - is the space inside the rectangle given in square units.
B. The 4 Basic Operations and Their Symbols
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Sum means to add: use +
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Difference means to subtract: use -
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Product means to multiply: use ( )( ), ·, 2( ), 5x
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Quotient means to divide: use ÷ or the fraction bar (¾)
Practice Problems
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G Redden
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