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### Course: Class 6 (Old)>Unit 1

Lesson 5: Estimating sum, difference, or product

# Estimating adding and subtracting 3-digit numbers

Use estimation to find reasonable solutions to addition and subtraction problems.

## Want to join the conversation?

• what does estimating mean
• Estimate means to think of , not the exact number, but a whole number closest to that number.
(1 vote)
• this doesn't help im getting it wrong all the time
• That should not happen. You mite not be getting it.
• how do you + - with a nummer line
• On a number line, anything to the right of 0 is a positive number (+) and anything to the left of 0 is a negative number (-). Hope this helps!
(1 vote)
• can you do a video that i can actually understand because i don't get it
• what is 400+22=
• It equals 422, the 22 takes the place of the two zeros:)
• How does he or she do it?
• E z !1
(1 vote)
• you guys think this is easy.This is hard.
(1 vote)
• when you round do you subtract the amount you rounded to get the correct answer and not the rounded answer?
(1 vote)
• what do you do when you round a decimal to the nearest ten
(1 vote)
• You either go up because the units are five (or greater) or go down because they're four or less than four. For example:

13.1 (approximately 13) is near to 10
16.7 (approximately 17) is near to 20
14.9 (approximately 15) is near to 20

Now if you had like 0.013 that's not close to ten, luckily you don't need to round small decimals to the nearest ten cause they're far from ten.
(1 vote)