Mary Jane Sterling - Algebra I All-in-One For Dummies

A.First change the 2 to a fraction: . Then change the divide to multiply and the second (right) fraction to its reciprocal. Then do the multiplication problem to get the answer , which can be changed to the mixed number.

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A complex fraction is a fraction within a fraction. If a fraction has another fraction in its numerator or denominator (or both), it’s called complex. Fractions with this structure are awkward to deal with and need to be simplified. To simplify a complex fraction, you first work at creating improper fractions or integers in the numerator and denominator, independently, and then you divide the numerator by the denominator. You need to boil this down to one term in the numerator and one in the denominator.

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A.First, change the mixed number in the numerator to an improper fraction. Then divide the two fractions by multiplying the numerator by the reciprocal of the denominator.

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A.First, find a common denominator for the fractions in the numerator and a separate one for those in the denominator. Then subtract the fractions in the numerator and add the fractions in the denominator. Finally, divide the two fractions by multiplying the numerator by the reciprocal of the denominator.

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Decimals are essentially fractions whose denominators are powers of 10. This property makes for much easier work when adding, subtracting, multiplying, or dividing.

When adding or subtracting decimal numbers, just line up the decimal points and fill in zeros, if necessary.

When multiplying decimals, just ignore the decimal points until you’re almost finished. Count the number of digits to the right of the decimal point in each multiplier, and the total number of digits is how many decimal places you should have in your answer.

Dividing has you place the decimal point first, not last. Make your divisor a whole number by moving the decimal point to the right. Then adjust the number you’re dividing into by moving the decimal point the same number of places. Put the decimal point in your answer directly above the decimal point in the number you’re dividing into (the dividend).

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A.Line up the decimal points in the first two numbers and add. Put in zeros to help you line up the digits. Then subtract the last number from the result.

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A.Multiply the first two numbers together, creating an answer with four decimal places to the right of the decimal point. Then divide the result by 0.6, after moving the decimal point one place to the right in both divisor and dividend.

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Decimals are nothing more than glorified fractions. Decimals are special because, when written as fractions, their denominators are always powers of 10 — for example, 10, 100, 1,000, and so on. Because decimals are such special fractions, you don’t even have to bother with the denominator part. Just write the numerator and use a decimal point to indicate that it’s really a fraction with a denominator that’s a power of 10.