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Lesson 1: Subtracting decimals intro

# 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
• 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.
• hi how do you know when to round
(1 vote)
• You will know when to round when the question tells you or not. 'Basically rounding is if the given number or calculated number ending with a 1,2,3 or 4 you round down. Though if the given number or calculated number ends with 5,6,7,8 or 9 you round up.'

Hope this helps!
(1 vote)
• thank you so much for this explanation it really helped me and my fellow class mates because of this video we are now getting so much more along thank you so much mr bal
(1 vote)
• you round to what the decimal is closer to like 5.7 is rounded to 6. 4.3 rounded is 4.
Do you understand that hamiltonfan53
(1 vote)
• 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).
(1 vote)