Big Ideas Math: Modeling Real Life, Grade 7
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Big Ideas Math: Modeling Real Life, Grade 7 View details
5. Dividing Rational Numbers
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Exercise 18 Page 77

Rewrite the expression so that all of the numbers are fractions. Dividing two fractions is the same as multiplying the first fraction by the reciprocal of the second fraction.

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Practice makes perfect
Before we evaluate the expression, let's first rewrite the expression so that all of the numbers are fractions.
- 10 27Ă· (- 4 411)
- 10* 7+2/7Ă· (- 4* 11+4/11)
- 70+2/7Ă· (- 44+4/11)
- 72/7Ă· (- 48/11)
Recall that dividing two fractions is the same as multiplying the first fraction by the reciprocal of the second fraction. - 72/7Ă· ( - 48/11) = - 72/7* ( - 11/48) When multiplying real numbers, the product will be positive if the signs are the same and it will be negative if the signs are different. cc Same Sign & Different Signs (+)(+)=(+) & (+)(-)=(-) (-)(-)=(+) & (-)(+)=(-) In our case both numbers are, so the product will be positive.
- 72/7* (- 11/48)
72/7* 11/48
When we multiply fractions, we need to remember that the product of two fractions is equal to the product of the numerators divided by the product of the denominators. Let's find the given product!
72/7* 11/48
72* 11/7* 48
792/336
792Ă· 24/336Ă· 24
33/14
The quotient is 3314. This is not the simplest form of this fraction because it is improper. Improper fractions can be written as mixed numbers.
33/14
28+5/14
28/14+5/14
2+5/14
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