Rounding And Estimation: Multiple Choice Questions & Answers

1. Patricia bought a dress for $23.99 and a coat for $47.50. What is the BEST way to estimate the total cost of the purchase?

$20+$40

$20+$50

$30+$40

$39+$50

To estimate the total cost of Patricia's purchase, it is best to round the prices of the dress and coat to the nearest tens place. Since the dress costs $23.99, rounding it to the nearest tens place gives us $20. Similarly, rounding the coat's price of $47.50 to the nearest tens place gives us $50. Therefore, the best way to estimate the total cost of the purchase is $20 + $50.

Explanation

To estimate the total cost of Patricia's purchase, it is best to round the prices of the dress and coat to the nearest tens place. Since the dress costs $23.99, rounding it to the nearest tens place gives us $20. Similarly, rounding the coat's price of $47.50 to the nearest tens place gives us $50. Therefore, the best way to estimate the total cost of the purchase is $20 + $50.

2. Round off to the nearest thousand place: 7379

7000

7500

8000

70000

The given number is 7379. To round off to the nearest thousand place, we look at the digit in the hundreds place, which is 3. Since 3 is less than 5, we round down and keep the thousands place as it is. Therefore, the rounded off number is 7000.

Explanation

The given number is 7379. To round off to the nearest thousand place, we look at the digit in the hundreds place, which is 3. Since 3 is less than 5, we round down and keep the thousands place as it is. Therefore, the rounded off number is 7000.

3. Mark wants to estimate the product of 293 and 724. What would be the BEST way to do so?

200 X 700

300 X 700

400 X 700

300 X 800

To estimate the product of 293 and 724, it would be best to round both numbers to the nearest hundred and then multiply them together. Rounding 293 to the nearest hundred gives us 300, and rounding 724 to the nearest hundred gives us 700. Multiplying 300 by 700 gives us an estimate of the product.

Explanation

To estimate the product of 293 and 724, it would be best to round both numbers to the nearest hundred and then multiply them together. Rounding 293 to the nearest hundred gives us 300, and rounding 724 to the nearest hundred gives us 700. Multiplying 300 by 700 gives us an estimate of the product.

4. Round to the nearest thousands place:
7,803,422.397

7,803,000

7,805,000

8,803,000

7,820,000

The given number, 7,803,422.397, needs to be rounded to the nearest thousands place. The thousands place is the digit immediately to the left of the decimal point. In this case, the digit in the thousands place is 3. Since the digit to the right of the thousands place is less than 5 (0.397), we round down. Therefore, the rounded number to the nearest thousands place is 7,803,000.

Explanation

The given number, 7,803,422.397, needs to be rounded to the nearest thousands place. The thousands place is the digit immediately to the left of the decimal point. In this case, the digit in the thousands place is 3. Since the digit to the right of the thousands place is less than 5 (0.397), we round down. Therefore, the rounded number to the nearest thousands place is 7,803,000.

5. Round off to the nearest hundreds place: 42782

42800

45000

43000

42000

The given number, 42782, is rounded off to the nearest hundreds place. Since the digit in the tens place (2) is less than 5, we round down the number. Therefore, the correct answer is 42800.

Explanation

The given number, 42782, is rounded off to the nearest hundreds place. Since the digit in the tens place (2) is less than 5, we round down the number. Therefore, the correct answer is 42800.

6. Round off to the nearest tens places: 71577

71500

71000

71580

72000

The given number, 71577, is rounded off to the nearest tens place. The digit in the tens place is 7, which is greater than 5. According to the rounding rule, when the digit in the tens place is 5 or greater, we round up. Therefore, the nearest tens place for 71577 is 71580.

Explanation

The given number, 71577, is rounded off to the nearest tens place. The digit in the tens place is 7, which is greater than 5. According to the rounding rule, when the digit in the tens place is 5 or greater, we round up. Therefore, the nearest tens place for 71577 is 71580.

7. A 2-digit number was rounded off to the nearest tens and the result came out as 70. Find the interval of the original number.

75 to 80

65 to 74

85 to 90

70 to 75

When a 2-digit number is rounded off to the nearest tens and the result is 70, it means that the original number is closer to 70 than to any other tens. To find the interval of the original number, we need to determine the range of numbers that are closer to 70. Since the original number is rounded off to the nearest tens, it could be anywhere from 65 to 74, as these are the numbers that are closest to 70. Therefore, the interval of the original number is 65 to 74.

Explanation

When a 2-digit number is rounded off to the nearest tens and the result is 70, it means that the original number is closer to 70 than to any other tens. To find the interval of the original number, we need to determine the range of numbers that are closer to 70. Since the original number is rounded off to the nearest tens, it could be anywhere from 65 to 74, as these are the numbers that are closest to 70. Therefore, the interval of the original number is 65 to 74.

8. Sophia wanted to estimate the product of 73 X 12 so she made a word problem of 70 X 10. Would her estimate be more or less than the actual estimate?

Less, because she rounded both numbers up

More, because she rounded both numbers up.

Less, because she rounded both numbers down.

Less, because she rounded both numbers up.

Sophia's estimate would be less than the actual estimate because she rounded both numbers down. When she rounded 73 down to 70 and 12 down to 10, she underestimated the actual values. Rounding down always results in a lower value, so her estimate would be less than the actual product of 73 X 12.

Explanation

Sophia's estimate would be less than the actual estimate because she rounded both numbers down. When she rounded 73 down to 70 and 12 down to 10, she underestimated the actual values. Rounding down always results in a lower value, so her estimate would be less than the actual product of 73 X 12.

9. Round these 2 numbers to the nearest hundreds place: 98 and 456

100, 500

100, 460

98, 540

98, 550

The given number, 98,456, needs to be rounded to the nearest hundreds place. The hundreds place is the second digit from the right, which is 5. Since the digit in the tens place is 5 or greater, we round up. Therefore, the rounded number is 100,500.

Explanation

The given number, 98,456, needs to be rounded to the nearest hundreds place. The hundreds place is the second digit from the right, which is 5. Since the digit in the tens place is 5 or greater, we round up. Therefore, the rounded number is 100,500.

10. Round to the nearest hundredths place: 9,765.248

9,860

9,700

9,765.24

9,765.25

The given number, 9,765.248, has a digit in the thousandths place (8), which is greater than or equal to 5. Therefore, when rounding to the nearest hundredths place, the digit in the hundredths place (4) is increased by 1 to become 5. Thus, the correct answer is 9,765.25.

Explanation

The given number, 9,765.248, has a digit in the thousandths place (8), which is greater than or equal to 5. Therefore, when rounding to the nearest hundredths place, the digit in the hundredths place (4) is increased by 1 to become 5. Thus, the correct answer is 9,765.25.

11. What is the BEST estimate for Klein to use to determine the difference of 19,320 and $9,876?

$7000

$9000

$10,000

$29,000

Klein can use $9,000 as the best estimate to determine the difference between 19,320 and $9,876. This is because $9,000 is the closest option to the actual difference, which is $9,444. Using $9,000 as an estimate would provide a reasonably accurate approximation of the difference between the two numbers.

Explanation

Klein can use $9,000 as the best estimate to determine the difference between 19,320 and $9,876. This is because $9,000 is the closest option to the actual difference, which is $9,444. Using $9,000 as an estimate would provide a reasonably accurate approximation of the difference between the two numbers.

12. Round to the nearest tenths place:
78.539

78.54

78.53

78.6

78.5

The given number, 78.539, has a digit in the hundredths place (3) that is less than 5. According to the rounding rule, when the digit in the hundredths place is less than 5, the digit in the tenths place (9) remains the same. Therefore, the correct answer is 78.5.

Explanation

The given number, 78.539, has a digit in the hundredths place (3) that is less than 5. According to the rounding rule, when the digit in the hundredths place is less than 5, the digit in the tenths place (9) remains the same. Therefore, the correct answer is 78.5.

13. What will be the estimate value of √98?

9.8

9.0

9.9

.99

The estimate value of √98 can be determined by finding the closest whole number to the square root of 98. The square root of 98 is approximately 9.899. Since 9.9 is the closest whole number to 9.899, it can be considered as the estimate value of √98.

Explanation

The estimate value of √98 can be determined by finding the closest whole number to the square root of 98. The square root of 98 is approximately 9.899. Since 9.9 is the closest whole number to 9.899, it can be considered as the estimate value of √98.

14. Round to the nearest tenths place: 52.588

52.57

52.58

52.59

52.6

When rounding a number to the nearest tenth place, we look at the digit immediately to the right of the tenths place, which is the hundredths place.

In this case, the digit in the hundredths place is 8. Since 8 is greater than or equal to 5, we round the digit in the tenths place (8) up by 1.

So, 52.588 rounded to the nearest tenth place is 52.6.

Explanation

When rounding a number to the nearest tenth place, we look at the digit immediately to the right of the tenths place, which is the hundredths place.

In this case, the digit in the hundredths place is 8. Since 8 is greater than or equal to 5, we round the digit in the tenths place (8) up by 1.

So, 52.588 rounded to the nearest tenth place is 52.6.

15. Michael Jordan scored a total of 32,292 points in his career. ABOUT how many points is that?

$29,000

$30,000

$31,000

$32,000

Based on the given information, Michael Jordan scored a total of 32,292 points in his career. The question asks for an estimation of how many points that is "about." Among the given options, $30,000 is the closest value to the actual number of points scored by Michael Jordan. Therefore, the answer is $30,000.

Explanation

Based on the given information, Michael Jordan scored a total of 32,292 points in his career. The question asks for an estimation of how many points that is "about." Among the given options, $30,000 is the closest value to the actual number of points scored by Michael Jordan. Therefore, the answer is $30,000.