Download Estimating Sums and Differences of Whole Numbers

Estimating Sums and
Differences of Whole
Numbers
You know how to round numbers. Today, you
will use rounding to estimate sums and
differences.
• What are some things that are often rounded?
Vera went on a 3 day trip in which she
traveled 336 miles on the first day, 423 on
the second day, and 357 miles on the third
day. Is 300 or 400 a more reasonable
estimate for about how far she went on
each of the 3 days?
What is each number rounded to the nearest
hundred?
What is the sum of the rounded numbers?
Estimate 518+271 by rounding to the nearest
hundred.
• Then, estimate the sum by rounding to the nearest ten.
• Which estimate is closer to the exact sum?
Round each number to the nearest hundred:
• 1,250 --
• +204--
• _________
• Then round to the nearest ten! Which estimate is closer!?
Please work on pages 94-95 # 1-30. You must
show your estimated numbers before adding!!!
• Go over work.
• Castle learning/Problem Solving