Section 1.5 - Rational Number Operations
Complete the following questions
- 1.
Calculate the expression: -3 2/3 + (-6 2/5)
- A.
-10 1/15
- B.
-9 14/15
- C.
-2 11/15
- D.
10 1/15
Correct Answer
A. -10 1/15Explanation
The given expression involves adding two mixed numbers. To add mixed numbers, we first add the whole numbers together and then add the fractions together. In this case, the whole numbers -3 and -6 add up to -9. The fractions 2/3 and 2/5 have different denominators, so we need to find a common denominator. The least common multiple of 3 and 5 is 15. We convert 2/3 to 10/15 and 2/5 to 6/15. Adding 10/15 and 6/15 gives us 16/15, which simplifies to 1 and 1/15. Therefore, the final answer is -9 1/15, which can also be written as -10 1/15.Rate this question:
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- 2.
When you multiply two numbers, which of the following will result in a negative product?
- A.
If both factors are negative
- B.
If one factor is negative and the other is 0
- C.
If both factors are positive
- D.
If one factor is negative and the other is postive
Correct Answer
D. If one factor is negative and the other is postiveExplanation
When you multiply two numbers, the product will be negative if one factor is negative and the other is positive. This is because when you multiply a positive number by a negative number, the result is always negative. Therefore, if one factor is negative and the other is positive, their product will be negative.Rate this question:
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- 3.
The temperature outside is -10 F. What is the temperature is degrees Celsius? Use the formula C = 5/9(F - 32) to convert to degrees Celsius.
- A.
-75.2 C
- B.
-23 1/3 C
- C.
-12 2/9 C
- D.
12 2/9 C
Correct Answer
B. -23 1/3 CExplanation
The correct answer is -23 1/3 C. To convert Fahrenheit to Celsius, we use the formula C = 5/9(F - 32). Plugging in -10 for F, we get C = 5/9(-10 - 32) = 5/9(-42) = -210/9 = -23 1/3 C.Rate this question:
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- 4.
Evaluate the expression (3/5 - 5/8) x (-2/3)
- A.
-1/30
- B.
-1/60
- C.
1/60
- D.
1/30
Correct Answer
C. 1/60Explanation
To evaluate the expression, we first need to simplify the fractions. The common denominator for 5 and 8 is 40, so we can rewrite 3/5 as 24/40 and 5/8 as 25/40. Next, we subtract these fractions to get -1/40. Finally, we multiply this result by -2/3, which gives us 2/120 or simplified as 1/60. Therefore, the correct answer is 1/60.Rate this question:
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- 5.
Evaluate the expression: -4.5(2.8)(3.6 - 1.9)
- A.
-34.02
- B.
-21.42
- C.
21.42
- D.
34.02
Correct Answer
B. -21.42Explanation
The given expression involves multiplication and subtraction. We start by subtracting 1.9 from 3.6, which gives us 1.7. Then, we multiply 2.8 by 1.7, resulting in 4.76. Finally, we multiply -4.5 by 4.76, giving us -21.42. Therefore, the correct answer is -21.42.Rate this question:
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- 6.
At a golf tournament the golfers has a mean score of -2.25. If there were 60 golfers in the tournament, what was their combined score?
- A.
-150
- B.
-135
- C.
135
- D.
150
Correct Answer
B. -135Explanation
The mean score of -2.25 indicates that, on average, each golfer scored -2.25. Since there were 60 golfers, their combined score can be calculated by multiplying the mean score by the number of golfers. Therefore, the combined score is -2.25 * 60 = -135.Rate this question:
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- 7.
Evaluate the expression: 2 3/8 x (-5/6) / (3/4)
- A.
-3 7/36
- B.
-2 23/36
- C.
-1 31/64
- D.
-5/19
Correct Answer
B. -2 23/36Explanation
The expression involves multiplication and division of mixed numbers. To simplify, we first convert the mixed numbers to improper fractions. Then we multiply 2 and 3/8 to get 19/8. Next, we multiply 19/8 by -5/6 to get -95/48. Finally, we divide -95/48 by 3/4, which is the same as multiplying by the reciprocal, 4/3. This gives us -380/144, which simplifies to -95/36 or -2 23/36.Rate this question:
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- 8.
What number makes this equation true: -2 1/2 x ____ = - 1
- A.
-1 1/2
- B.
-2/5
- C.
2/5
- D.
1 1/2
Correct Answer
C. 2/5Explanation
To find the missing number in the equation, we need to isolate it. We can start by multiplying both sides of the equation by the reciprocal of -2 1/2, which is -2/5. This cancels out the fraction on the left side, leaving us with just the missing number. On the right side, -1 multiplied by -2/5 is equal to 2/5. Therefore, the missing number that makes the equation true is 2/5.Rate this question:
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- 9.
The low temperature was - 25 C in January. What was the low temperature in degrees Fahrenheit? Use the formula F = 9/5C + 32 to convert to degrees Fahrenheit
- A.
-102.6 F
- B.
-13 F
- C.
8.8 F
- D.
12.6 F
Correct Answer
B. -13 FExplanation
To convert the temperature from Celsius to Fahrenheit, we can use the formula F = (9/5)C + 32. In this case, the Celsius temperature is -25. Plugging this value into the formula, we get F = (9/5)(-25) + 32 = -45 + 32 = -13. Therefore, the low temperature in degrees Fahrenheit is -13 F.Rate this question:
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Mar 17, 2023Quiz Edited by
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Jan 31, 2009Quiz Created by
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