Mark wants to round to the nearest hundred to estimate the sum of 271 and 582. He wrote 270 + 580 = 850.

Part A
What mistake did Mark make?
A.
00:00

Mark should have rounded 271 to 250 and rounded 582 to 550: 250 + 550 = 800.
B.
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Mark should have rounded 271 to 250 and rounded 582 to 600: 250 + 600 = 850.
C.
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Mark should have rounded 271 to 300 and rounded 582 to 500: 300 + 500 = 800.
D.
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Mark should have rounded 271 to 300 and rounded 582 to 600: 300 + 600 = 900.
00:00

Part B
What is the sum of 271 and 582 rounded to the nearest hundred?
A.300
B.850
C.900
D.1,000

Step-by-step explanation:

Part A:

Mark did not round to the nearest hundreds, he rounded to the nearest tens.

Option A (Incorrect):

271 and 582 are normally not rounded down, unless we are using limits coming from the left and a unique equation.

Option B (Incorrect):

271 as the same problem as option A, but 582 rounding to 600 is correct. It doesn't make sense to round both numbers differently, unless stated.

Option C (Incorrect):

271 rounding to 300 is correct, but 582 is not normally rounded down to 500 unless we are using limits coming from the left and a unique equation. Unless stated, don't round both numbers differently.

Option D (Correct):

271 rounded to 300 and 582 rounded to 600 looks correct for rounding to the hundreds.

Part B:

There are two ways to solve this question:

One way:

271 + 582 = 853

Round 853 to the nearest hundred for 900

(Note: Round 853 to the nearest tens for 850.)

Second way:

271 + 582

Round Numbers:

300 + 600

= 900

the number of possible outcomes that do not show a 1 on the first spinner and show the number 4 on the second spinner is 2.

spinner 1 spinner 2

1                     1

1                     2

1                     3

1                     4

2                   1

2                   2

2                   3

2                   4   = not 1, and 4

3                   1

3                   2

3                   3

3                   4 = not 1, and 4

only 2 outcomes have passed the given condition.

step-by-step explanation: