Question 1

278.4132987 × 0.2617944285 is about:
A) 7.
B) 70.
C) 700.
D) 7000.
E) 70,000.

Accepted Answer

To estimate the product of 278.4132987 × 0.2617944285, we can round the numbers to 280 and 0.26, respectively. Multiplying these gives 72.8, which is approximately 70.

Question 2

0.3347876 × 629.847291143 is CLOSEST to:
A) 1800.
B) 180.
C) 200.
D) 210.
E) 240.

Accepted Answer

The answer of 0.3347876 × 629.847291143 is CLOSEST to:
A) 1800.
B)...

Question 3

Use number sense in locating the decimal point in the answer. Explain your thinking briefly.
A) 77.5 × 2.84 = 2 2 0 1
B) 1002.6 ÷ 3.6 = 2 7 8 5

Accepted Answer

The answer of Use number sense in locating the decimal...

Question 4

You are using a calculator that can show only eight digits of an answer. When you finish, you realize that you forgot to press the decimal points in the original numbers. Show where the decimal points go and explain how you know, using number sense (no paper-pencil calculation).
A) 9.87429 × 637.21945 = 6 2 9 2 0 8 9 6
B) 413.69824 ÷ 24.92617 = 1 6 5 9 6 9 4 4

Accepted Answer

The answer of You are using a calculator that can...

Question 5

Demonstrate number sense in estimating the following expressions and responding to the question about your answer. Write enough to make your thinking clear.
75.48% × 883.375 × 567/566 is about _____.
Is your estimate less than, equal to, greater than the exact answer? Why? (Don't figure the exact answer out!) _____

Accepted Answer

The answer of Demonstrate number sense in estimating the following...

Question 6

Company X bought 17,569 truckloads worth $24,598 each. Company Y bought 24,598 truckloads worth $17,569 each. Which company paid more?
A) The companies paid the same.
B) Company X paid more.
C) Company Y paid more.

Accepted Answer

Both companies paid the same amount because the product of the number of truckloads and the cost per truckload is the same for both companies (17,569 * $24,598 = 24,598 * $17,569).

Question 7

Betty was asked to give her best estimate for 25% of 7991.8. She estimates by taking 1/4 of 8000, which is 2000, and taking 1/4 of 0.8, which is 0.2. Therefore, her estimate is 2000.2. Comment on Betty's reasoning.

Accepted Answer

The answer of Betty was asked to give her best...

Question 8

42,189 ÷ 511,264 is about how many percent?
A) 8%
B) 12.5%
C) 80%
D) 125%
E) 1.25%

Accepted Answer

The answer of 42,189 ÷ 511,264 is about how many...

Question 9

Estimate each calculation with a brief explanation.
A) 65% of 37
B) 140% of 52
C) 18% of 971
D) 8/9% of 120 = _____ (decimal)

Accepted Answer

The answer of Estimate each calculation with a brief explanation.
A)...

Question 10

Use benchmarks to estimate each calculation. Explain how you arrived at the estimate.
A) 60% of $271
B) 87 × 52
C) 32% of $595.45

Accepted Answer

The answer of Use benchmarks to estimate each calculation. Explain...

Question 11

Estimate the indicated quantity and tell how you did it.
A) 15% of $51.07
B) 25% of 1998
C) 125% of 47
D) 48% of 212
E) 4% of 201

Accepted Answer

The answer of Estimate the indicated quantity and tell how...

Question 12

Name an item that costs approximately $500,000.
A) a family car
B) a private jet
C) a nice home
D) a stereo

Accepted Answer

A nice home can cost approximately $500,000, depending on the location and market conditions.

Question 13

Name two types of estimates you use in daily life.

Accepted Answer

The answer of Name two types of estimates you use...

Question 14

Using benchmarks, what is the BEST estimate of the time it would take, averaging 50 mph for 8 hours a day, to drive across the United States (about 3000 miles)?
A) 6.25 driving days
B) 7$\frac { 1 } { 2 }$ driving days
C) 400 driving days

Accepted Answer

At 50 mph for 8 hours a day, you would cover 400 miles per day (50 mph * 8 hours). To cover 3000 miles, it would take 3000 miles / 400 miles per day = 7.5 days.

Question 15

Write in scientific notation.
A) 38,000,000,000
B) 382.45
C) 0.000 000 000 456

Accepted Answer

The answer of Write in scientific notation.
A) 38,000,000,000
B) 382.45
C) 0.000...

Question 16

Write each value in scientific notation.
A) The Earth is 150,000,000,000 meters from the sun.
B) The speed of light is 300,000,000 meters per second.
C) A dust particle is 0.000 000 000 753 kg.

Accepted Answer

The answer of Write each value in scientific notation.
A) The...

Question 17

How many seconds does it take light to reach the Earth from the sun? Express your answer in scientific notation. (The Earth is 150,000,000,000 meters from the sun, and the speed of light is 300,000,000 meters per second.)

Accepted Answer

The answer of How many seconds does it take light...

Question 18

Kyle estimated that 23 × 31 was 603. Use a rectangular area model to illustrate the misunderstanding and the correct product.

Accepted Answer

The answer of Kyle estimated that 23 × 31 was...

Quiz 5: Using Numbers in Sensible Ways

278.4132987 × 0.2617944285 is about:

0.3347876 × 629.847291143 is CLOSEST to:

Use number sense in locating the decimal point in the answer. Explain your thinking briefly. A) 77.5 × 2.84 = 2 2 0 1 B) 1002.6 ÷ 3.6 = 2 7 8 5

Company X bought 17,569 truckloads worth $24,598 each. Company Y bought 24,598 truckloads worth $17,569 each. Which company paid more?

Betty was asked to give her best estimate for 25% of 7991.8. She estimates by taking 1/4 of 8000, which is 2000, and taking 1/4 of 0.8, which is 0.2. Therefore, her estimate is 2000.2. Comment on Betty's reasoning.

42,189 ÷ 511,264 is about how many percent?

Estimate each calculation with a brief explanation. A) 65% of 37 B) 140% of 52 C) 18% of 971 D) 8/9% of 120 = _____ (decimal)

Use benchmarks to estimate each calculation. Explain how you arrived at the estimate. A) 60% of $271 B) 87 × 52 C) 32% of $595.45

Estimate the indicated quantity and tell how you did it. A) 15% of $51.07 B) 25% of 1998 C) 125% of 47 D) 48% of 212 E) 4% of 201

Name an item that costs approximately $500,000.

Name two types of estimates you use in daily life.

Using benchmarks, what is the BEST estimate of the time it would take, averaging 50 mph for 8 hours a day, to drive across the United States (about 3000 miles) ?

Write in scientific notation. A) 38,000,000,000 B) 382.45 C) 0.000 000 000 456

Write each value in scientific notation. A) The Earth is 150,000,000,000 meters from the sun. B) The speed of light is 300,000,000 meters per second. C) A dust particle is 0.000 000 000 753 kg.

How many seconds does it take light to reach the Earth from the sun? Express your answer in scientific notation. (The Earth is 150,000,000,000 meters from the sun, and the speed of light is 300,000,000 meters per second.)

Kyle estimated that 23 × 31 was 603. Use a rectangular area model to illustrate the misunderstanding and the correct product.