This document provides steps for estimating the sum of two or more numbers by rounding the addends. It explains that rounding the addends allows you to determine the place value of the estimated sum. Examples are provided to demonstrate rounding addends with ones and tens places to then solve the estimate and identify the place value of the actual sum. Additional practice problems apply these steps and show the estimated place value of the answer.

1. Estimating Sum

2. Terms
• Sum – Answer to addition.
• Addends – The numbers that are being
added
• Estimate – An estimate to the answer of a
problem; it tells you whether the answer is
the tenths, ones, tens, hundreds,
thousands . . .

3. Steps
• Sample Problem: 14 + 17 = ?
• Round each of the addends so that there
is one number followed by zero(es).
Ex. 14 -> 10
+ 17 -> 20
• Solve the estimate to find the place value
of the sum.
10 + 20 = 30; the answer is in the tens.
14 + 17 = 31; the actual sum

4. Additional Practice
1. 18 + 21 =
2. 27 + 6,245
3. 99 + 21
4. 22 + 28
1. 20 + 20 = 40
The answer is in the hundreds.
2. 30 + 6,000 = 6,030
The answer is in the thousands.
3. 100 + 20 = 120
The answer is in the hundreds
4. 20 + 30 = 50
The answer is in the tens

5. 568 187
+ 27 + 56
1648 16
+ 43 + 13
600
+ 30
630
2000
+ 40
2,040
200
+ 60
260
20
+ 10
30

6. Let’s try this together.
337 71 4381 634
+ 13 + 13 + 41 + 12