Читать книгу Basic Math & Pre-Algebra All-in-One For Dummies (+ Chapter Quizzes Online) - Mark Zegarelli - Страница 78

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(a)

(b)

(c)

(d)

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(a)

(b)

(c)

(d)

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(a)

(b)

(c)

(d)

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(a) 110. Rewrite as its inverse: . Therefore,

(b) 15. Rewrite as its inverse: So, .

(c) 87. Rewrite using the commutative property: . Now rewrite this equation as its inverse: . Therefore, .

(d) 203. Rewrite by switching around the two numbers next to the equal sign: . So, .

(e) 81. Rewrite using the commutative property: . Now rewrite this equation as its inverse: . So, .

(f) 20. Rewrite by switching around the two numbers next to the equals sign: . So, .

5 58. First, do the multiplication inside the parentheses:

Now add: .

6 123. First, do the subtraction inside the parentheses:

Now simply divide .

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(a)

(d)

Yes, the placement of parentheses changes the result.

8

(a)

(b)

No, because of the associative property of addition, the placement of parentheses doesn’t change the result.

9

(a)

(b)

No, because of the associative property of multiplication, the placement of parentheses doesn’t change the result.

10 937,690. The problem is easiest to solve by placing parentheses around :

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(a)

(b)

(c)

(d)

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(a)

(b)

(c)

(d)

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(a)

(b)

(c)

(d) . You already know from part c that , so multiply this number by 2 to get your answer: .

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(a) 10,000. Write 1 followed by four 0s.

(b) 10,000,000,000. Write 1 followed by ten 0s.

(c) 1,000,000,000,000,000. Write 1 followed by fifteen 0s.

(d) 10. Any number raised to the power of 1 is that number.

In the next section, the chapter quiz gives you a chance to practice the skills you learned in this chapter.