Success step english 3 pdf

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1. Locate the place. If the question calls for rounding to the nearest ten, look at the tens place. Notice the place

digit. Realize that the place digit will either stay the same or go up one.

2. Look at the digit to the right of the place digit—the right-hand neighbor.

3. If the right-hand neighbor is less than 5, the place digit stays the same.

4. If the right-hand neighbor is 5 or more, the place digit goes up one.

5. If the place digit is 9, and the right-hand neighbor is 5 or more, then turn the place digit to 0 and raise the

left-hand neighbor up one.

6. If instead of a place, the question calls for rounding to a certain number of significant digits, count that num￾ber of digits starting from the left to reach the place digit. Now start with step 1.

7. If the specified place was to the left of the decimal point, change all the digits to 0 that are to the right of the

place digit.

3. The digit is 9; the 9 will either stay 9 or go to 0.

The number 6 is to the right of 9; it is more than

5, so change 9 to 0 and apply step 5, raising the 2

to the left of 9 to 3. Now apply step 7, and change

digits to the right of the tens place to 0. The

answer is 300.

4. Here you need to apply step 6. Two places from

the left is the ten thousands digit, a 4. Now apply

step 1 and work through the steps: The digit is 4,

so it will either stay 4 or go up to 5. Since the

right-hand neighbor is 5, change the 4 to 5. Now

apply step 7 and change all digits to the right of

your new 5 to zero. The answer is 350,000.

Estimation

Estimation requires rounding numbers before adding,

subtracting, multiplying, or dividing. If you are given

numerical answers, you might just want to multiply

the two numbers without estimation and pick the

answer that is the closest. Most likely, however, the

problem will be more complicated than that.

Sample Estimation Question

5. 42 × 57 is closest to

a. 45 × 60.

b. 40 × 55.

c. 40 × 50.

d. 40 × 60.

e. 45 × 50.

Answer to Sample Estimation Question

Here’s how you could use the steps to answer the sam￾ple question:

1. You can round 42 down and 57 up, resulting in

answer d.

2. Rounding the numbers to one significant digit

yields d also.

3. Eliminate. a. Eliminated: 45 is further from 42

than is 40. b. Maybe. c. Eliminated: 50 is further

from 57 than is 60. e. Eliminated: 45 is further

from 42 and 50 is further from 57.

4. Check the remaining answers. The product of

choice b is 2,200. The product of choice d is

2,400. The actual product is 2,394, which makes

d the closest, and therefore the correct answer.

Seven Success Steps for Rounding Questions