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# Estimating decimal subtraction

This video is all about learning to estimate when subtracting decimals. It emphasizes the importance of rounding to the nearest whole number and doing quick mental calculations to get an approximate answer. It's all about getting comfortable with estimation!

## Want to join the conversation?

• but how do you know if you round up or down?
• You look on the digit on the right of the one you're rounding. If that digit is 5, 6, 7, 8 or 9 you round up. If it's 0, 1, 2, 3, 4 you round down.

That's all, hope that helps.
• Thank you for helping a lot it was really easy after I learned
• bruh this stuff hard no cap.
• na bro you caping is easy no cap
(1 vote)
• the whole numbers it is closest to
• ya if it is hiyer then 5 you round up if it is 4 or lower you round down.
• wow I now understand
• I don’t understand
• so for example 7.93-6.12 is close to 8-6,which is 2. 0.5 or larger round up, 0.49 or smaller round down.
• how do u subtract 7.7 from 3.11? it doesn't explain here
(1 vote)
• Since 3.11 has two decimal points, and 7.7 has one, you can add a 0 at the end of 7.7 to make 7.70. With that, you can simply just flip the terms to make the equation 7.70 - 3.11, where you subtract 3.11 from 7.70 which is equal to 4.59. However, subtracting 7.70 from 3.11 will not result in a positive number. As a result, you will add a negative sign in front of your number, to get your solution of - 4.59 (negative 4.59).