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Learn all about how to estimate when adding decimals. Practice rounding to the nearest whole number and how this can help us get a close approximation of the actual answer.

## Want to join the conversation?

• What is the difference between estimating and rounding.
• Estimating is finding the answer by rounding and rounding... well, rounding is just rounding
• decimals are easy, who's with me
• i have a test tomorrow and it's about estmating decimal sums and diffrences,adding decimals using mental math,adding decimals by regrouping,exploring problems that invlove decimals, and subtracting decimals by renaming! idon't get any of that so how should i study??
• but, from where u bring the 8
• He doesn’t bring an 8
• there is a pattern 19,10,9. like 10+9=19
• Yes, but does that have anything to do with quantum mechanics?
• what now? i dont even know! oof me
• In , you said that wrong. You were supposed to say: "Here were told five point 1.
• this is hard. why. someone please help me understand the back ground to this. any help.
• Hi ahm3021139
this is easy if you know how to round.
so 1.64 + 2.4 is equal to 4, if you take out the .04 part. that means you need to round it down to the nearest tenth to make it equal to 4. 1.64 + 2.4 is approximately equal to 4, because if you round to the nearest tenth, it's 1.6 + 2.4.
• When you add a decimal is it like normal stacking addition?
(1 vote)
• Yes you can use normal stacking addition for decimals, but make sure to line up the decimal points and put a decimal point directly underneath them in the answer.

Have a good day!