Big Ideas Math: Modeling Real Life, Grade 7
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Big Ideas Math: Modeling Real Life, Grade 7 View details
Cumulative Practice

Exercise 6 Page 122

To divide two decimal numbers, multiply the divisor and the dividend by the same power of 10 so that the divisor is a whole number.

4

We want to divide two decimal numbers. - 0.28÷(- 0.07) First, we can recall that a quotient of two negative numbers is positive. This means that we can rewrite our expression as a quotient of 0.28 and 0.07. - 0.28÷(- 0.07) ⇔ 0.28 ÷ 0.07 The calculations are easier if we multiply the divisor and the dividend by the same power of 10 so that the divisor is a whole number. In this case, we will multiply by 100. 0.28* 100 &= 28 0.07* 100 &= 7 This means that 0.28÷ 0.07 is the same as 28÷ 7. Now we will find the quotient. We divide, multiply, subtract, and compare as many times as we need.
Since 28÷ 7=4, we know that 0.28÷ 0.07=4. In this case, - 0.28÷ (- 0.07) is also equal to 4.