15 + 3(7 + 1) - 12?
- A. 21
- B. 25
- C. 27
- D. 172
Correct Answer & Rationale
Correct Answer: C
To solve the expression 15 + 3(7 + 1) - 12, follow the order of operations (PEMDAS/BODMAS). First, calculate the expression inside the parentheses: 7 + 1 equals 8. Next, multiply by 3: 3 * 8 equals 24. Now, add 15: 15 + 24 equals 39. Finally, subtract 12: 39 - 12 equals 27. Option A (21) is incorrect as it does not account for the multiplication. Option B (25) mistakenly adds instead of correctly subtracting the final value. Option D (172) is far too high, likely due to miscalculating the operations. Thus, the final result is 27, confirming option C as the correct choice.
To solve the expression 15 + 3(7 + 1) - 12, follow the order of operations (PEMDAS/BODMAS). First, calculate the expression inside the parentheses: 7 + 1 equals 8. Next, multiply by 3: 3 * 8 equals 24. Now, add 15: 15 + 24 equals 39. Finally, subtract 12: 39 - 12 equals 27. Option A (21) is incorrect as it does not account for the multiplication. Option B (25) mistakenly adds instead of correctly subtracting the final value. Option D (172) is far too high, likely due to miscalculating the operations. Thus, the final result is 27, confirming option C as the correct choice.
Other Related Questions
Cost of 3 cans of peaches is $2.67. Cost of 8 cans?
- A. $5.34
- B. $7.12
- C. $8.01
- D. $21.36
Correct Answer & Rationale
Correct Answer: B
To determine the cost of 8 cans of peaches, first calculate the cost per can. The cost of 3 cans is $2.67, so the cost per can is $2.67 ÷ 3 = $0.89. To find the cost of 8 cans, multiply the cost per can by 8: $0.89 × 8 = $7.12. Option A ($5.34) incorrectly assumes a lower total based on miscalculated per can pricing. Option C ($8.01) slightly overestimates the total, likely from rounding errors. Option D ($21.36) suggests a misunderstanding of basic multiplication, as it implies a much higher price than calculated. Thus, $7.12 accurately reflects the cost for 8 cans.
To determine the cost of 8 cans of peaches, first calculate the cost per can. The cost of 3 cans is $2.67, so the cost per can is $2.67 ÷ 3 = $0.89. To find the cost of 8 cans, multiply the cost per can by 8: $0.89 × 8 = $7.12. Option A ($5.34) incorrectly assumes a lower total based on miscalculated per can pricing. Option C ($8.01) slightly overestimates the total, likely from rounding errors. Option D ($21.36) suggests a misunderstanding of basic multiplication, as it implies a much higher price than calculated. Thus, $7.12 accurately reflects the cost for 8 cans.
Which student wrote the estimate closest to 1,592 + 8?
- A. Isabella
- B. Jayden
- C. Michael
- D. Sarah
Correct Answer & Rationale
Correct Answer: A
Isabella's estimate of 1,592 + 8 is 1,600, which is closest to the actual sum. This estimation rounds 1,592 to 1,590 and adds 10 for simplicity, yielding 1,600. Jayden likely underestimated or rounded incorrectly, resulting in a less accurate estimate. Michael may have rounded too far or added an incorrect value, leading to a larger discrepancy. Sarah's estimate might not have accounted properly for the addition, causing it to stray further from the actual result. Thus, Isabella’s approach demonstrates the most accurate estimation strategy.
Isabella's estimate of 1,592 + 8 is 1,600, which is closest to the actual sum. This estimation rounds 1,592 to 1,590 and adds 10 for simplicity, yielding 1,600. Jayden likely underestimated or rounded incorrectly, resulting in a less accurate estimate. Michael may have rounded too far or added an incorrect value, leading to a larger discrepancy. Sarah's estimate might not have accounted properly for the addition, causing it to stray further from the actual result. Thus, Isabella’s approach demonstrates the most accurate estimation strategy.
Which would be read as 'two million three hundred six thousand nine hundred thirty-four'?
- A. 2,036,934
- B. 2,306,934
- C. 2,360,934
- D. 2,369.03
Correct Answer & Rationale
Correct Answer: B
Option B, 2,306,934, accurately represents 'two million three hundred six thousand nine hundred thirty-four.' The number is broken down as follows: 2 million (2,000,000), 300 thousand (300,000), 6 thousand (6,000), 900 (900), and 30 (30), culminating in 2,306,934. Option A, 2,036,934, incorrectly includes only 30 thousand instead of 300 thousand. Option C, 2,360,934, misplaces the hundreds, showing 360 thousand instead of 306 thousand. Option D, 2,369.03, is not a whole number representation and introduces decimal values, which are irrelevant in this context.
Option B, 2,306,934, accurately represents 'two million three hundred six thousand nine hundred thirty-four.' The number is broken down as follows: 2 million (2,000,000), 300 thousand (300,000), 6 thousand (6,000), 900 (900), and 30 (30), culminating in 2,306,934. Option A, 2,036,934, incorrectly includes only 30 thousand instead of 300 thousand. Option C, 2,360,934, misplaces the hundreds, showing 360 thousand instead of 306 thousand. Option D, 2,369.03, is not a whole number representation and introduces decimal values, which are irrelevant in this context.
Joe’s age 4 more than 3x Amy’s. Equation?
- A. A=J/3+4
- B. A=3J+4
- C. J=3A+4
- D. J=3(A+4)
Correct Answer & Rationale
Correct Answer: C
To find the equation representing Joe's age in relation to Amy's, we start with the statement: Joe's age (J) is 4 more than 3 times Amy's age (A). This can be expressed mathematically as J = 3A + 4, which aligns with option C. Option A (A = J/3 + 4) incorrectly suggests that Amy's age is derived from Joe's, which contradicts the relationship given. Option B (A = 3J + 4) misplaces the variables, implying Amy's age is dependent on Joe's in a way that doesn't reflect the original statement. Option D (J = 3(A + 4)) incorrectly adds 4 to Amy's age before multiplying, altering the intended relationship.
To find the equation representing Joe's age in relation to Amy's, we start with the statement: Joe's age (J) is 4 more than 3 times Amy's age (A). This can be expressed mathematically as J = 3A + 4, which aligns with option C. Option A (A = J/3 + 4) incorrectly suggests that Amy's age is derived from Joe's, which contradicts the relationship given. Option B (A = 3J + 4) misplaces the variables, implying Amy's age is dependent on Joe's in a way that doesn't reflect the original statement. Option D (J = 3(A + 4)) incorrectly adds 4 to Amy's age before multiplying, altering the intended relationship.