Nokea
Solve this equation:
2x+8=0
- A. -4
- B. 3
- C. 5
Correct Answer: A
Rationale: To solve
2
x
+
8
=
0
2x+8=0:
Subtract 8 from both sides:
2
x
=
−
8
2x=−8
Divide both sides by 2:
x
=
−
8
2
=
−
4
x=
2
−8
​
=−4
Therefore, the solution is
x
=
−
4
x=−4.
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Bernard can make $80 per day. If he needs to make $300 and only works full days, how many days will this take?
- A. 2
- B. 3
- C. 4
- D. 5
Correct Answer: C
Rationale: To find out how many days Bernard needs to work to make $300, we divide the total amount he needs by how much he makes per day: $300 / $80 = 3.75 days. Since Bernard can only work full days, he would need to work for 4 days to make $300. Therefore, the correct answer is 4 days. Choice A (2 days) is incorrect because it does not match the calculation based on his daily earnings. Choice B (3 days) is incorrect as the calculated result is not a whole number, so Bernard needs to work for more than 3 days. Choice D (5 days) is incorrect as it exceeds the calculated number of days needed to make $300.
A student gets an 85% on a test with 20 questions. How many answers did the student solve correctly?
- A. 15
- B. 16
- C. 17
- D. 18
Correct Answer: C
Rationale: To determine the number of questions the student solved correctly, we need to calculate 85% of the total number of questions. This can be done by multiplying the total number of questions by 85%, which is 20 questions x 85% = 20 x 0.85 = 17 questions. Therefore, the student solved 17 questions correctly. Choice A, 15, is incorrect as it does not reflect the correct percentage of questions solved. Choice B, 16, and Choice D, 18, are also incorrect as they do not match the calculation based on the given percentage.
At the beginning of the day, Xavier has 20 apples. At lunch, he meets his sister Emma and gives her half of his apples. After lunch, he stops by his neighbor Jim's house and gives him 6 of his apples. He then uses ¾ of his remaining apples to make an apple pie for dessert at dinner. At the end of the day, how many apples does Xavier have left?
- A. 4
- B. 6
- C. 2
- D. 1
Correct Answer: D
Rationale: Xavier starts with 20 apples. He gives half of his apples to his sister Emma, which is 20 · 2 = 10 apples, leaving him with 10 apples. Then, he gives 6 apples to his neighbor Jim, leaving him with 10 - 6 = 4 apples. Using ¾ of his remaining 4 apples for the pie, he uses 3/4 x 4 = 3 apples. Therefore, he has 4 - 3 = 1 apple left at the end of the day. Choice D, 1 apple, is the correct answer. Choices A, B, and C are incorrect because Xavier ends up with 1 apple remaining, not 4, 6, or 2.
This chart indicates the number of sales of CDs, vinyl records, and MP3 downloads that occurred over the last year. Approximately what percentage of the total sales was from CDs?
- A. 55%
- B. 25%
- C. 40%
- D. 5%
Correct Answer: C
Rationale: To determine the percentage of CD sales out of the total sales, we need to consider the total sales of CDs, vinyl records, and MP3 downloads. To find the percentage of CD sales, we divide the total sales of CDs by the sum of total sales of CDs, vinyl records, and MP3 downloads, and then multiply by 100. In this case, the correct calculation shows that CDs accounted for 40% of the total sales. Choice A (55%) is incorrect as it overestimates the contribution of CDs. Choice B (25%) is incorrect as it underestimates the percentage of CD sales. Choice D (5%) is also incorrect as it severely underestimates the share of CD sales in the total sales.
Which of the following numbers has the greatest value?
- A. 1.4378
- B. 1.07548
- C. 1.43592
- D. 0.89409
Correct Answer: B
Rationale: To determine the number with the greatest value among the options, focus on the digit in the tenths place. In this case, 1.07548 has the highest value as it has the digit 7 in the tenths place. Comparing this to the other numbers, 1.4378, 1.43592, and 0.89409 have 4, 3, and 8 in the tenths place, respectively. Therefore, 1.07548 is the number with the greatest value as it has the highest digit in the tenths place.