Simplify the following expression: 5 x 3 · 9 x 4
- A. 5/12
- B. 8/13
- C. 20/27
- D. 47/36
Correct Answer: A
Rationale: To simplify the expression 5 x 3 · 9 x 4, first perform the multiplications and divisions from left to right: 5 x 3 = 15 and 9 x 4 = 36. So, the expression becomes 15 · 36. When dividing fractions, multiply the first fraction by the reciprocal of the second fraction. Hence, 15 · 36 = 15/36. To simplify the fraction further, find the greatest common divisor, which is 3. Divide both the numerator and denominator by 3 to get the final result: 15/36 = 5/12. Therefore, the correct answer is A. Choices B, C, and D are incorrect because they do not represent the correct simplification of the given expression.
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A patient requires a 20% decrease in medication dosage. Their current dosage is 400 mg. What will their dosage be after the decrease?
- A. 60 mg
- B. 80 mg
- C. 120 mg
- D. 320 mg
Correct Answer: B
Rationale: To calculate a 20% decrease of 400 mg, you multiply 400 mg by 0.20 to get 80 mg. Subtracting 80 mg from the current dosage of 400 mg results in a new dosage of 320 mg. Choice A is incorrect because it miscalculates the decrease. Choice C is incorrect as it represents a 20% increase instead of a decrease. Choice D is incorrect as it represents the initial dosage, not the reduced dosage.
Simplify the following expression: 4 * (2/3) · 1 * (1/6)
- A. 2
- B. 3 1/3
- C. 4
- D. 4 1/2
Correct Answer: C
Rationale: To simplify the expression, first convert the mixed numbers into fractions: 4 * (2/3) · 1 * (1/6). This becomes 4 * 2/3 · 1 * 1/6. Next, perform the multiplication and division from left to right: 8/3 · 1 * 1/6 = 8/3 * 1 * 6 = 8/3 * 6 = 16. Therefore, the correct answer is 4. Choice A (2) is incorrect as it does not represent the final simplified expression. Choice B (3 1/3) is incorrect as it does not match the result of simplifying the expression. Choice D (4 1/2) is incorrect as it does not match the result of simplifying the expression.
Robert is planning to drive 1,800 miles on a cross-country trip. If his car gets 30 miles per gallon and his tank holds 12 gallons of gas, how many tanks of gas will he need to complete the trip?
- A. 3 tanks
- B. 5 tanks
- C. 30 tanks
- D. 60 tanks
Correct Answer: B
Rationale: To find out how many tanks of gas Robert needs for the 1,800-mile trip, first, we calculate the distance his car can travel on a full tank: 30 miles per gallon 12 gallons = 360 miles per tank. Next, divide the total trip distance by the distance per tank: 1,800 miles · 360 miles per tank = 5 tanks. Therefore, Robert will need 5 tanks of gas to complete the cross-country trip. Choices A, C, and D are incorrect as they do not accurately calculate the number of tanks needed based on the given information.
The second midwife allocates 1/2 of her funds to pay an office administrator, plus another 1/10 for office supplies. What is the total fraction of the second midwife's budget that is spent on the office administrator and office supplies?
- A. 3/5
- B. 2/12
- C. 2/20
- D. 1/20
Correct Answer: A
Rationale: To find the total fraction of the second midwife's budget spent on the office administrator and office supplies, add the fractions. The midwife allocates 1/2 of her funds to the office administrator (1/2) and another 1/10 for office supplies. Adding 1/2 and 1/10 gives a total of 3/5. Choice A (3/5) is correct. Choice B (2/12) is incorrect as it simplifies to 1/6, which is not the total fraction. Choice C (2/20) is incorrect as it simplifies to 1/10, which is only the fraction spent on office supplies, not the total. Choice D (1/20) is incorrect as it represents only the fraction spent on office supplies, not the total spent on both the administrator and supplies.
Between the years 2000 and 2010, the number of births in the town of Daneville increased from 1432 to 2219. What is the approximate percent increase in the number of births?
- A. 55%
- B. 36%
- C. 64%
- D. 42%
Correct Answer: A
Rationale: To calculate the percent increase, subtract the initial value from the final value, which gives 2219 - 1432 = 787. Then, divide the increase (787) by the initial value (1432) and multiply by 100 to get the percentage: (787/1432) * 100 = 55%. Therefore, the approximate percent increase in the number of births is 55%. Choice B, 36%, is incorrect because it does not match the calculated increase. Choice C, 64%, is incorrect as it is higher than the actual percentage. Choice D, 42%, is incorrect as it is lower than the actual percentage.