Hello fellow maths people,(adsbygoogle = window.adsbygoogle || []).push({});

I studied a lot of maths at uni but I'm recently into doing some mental maths. I'm wondering, does anyone have any good mental techniques for doing 3 digit subtraction? For example:

Whats:

452 - 376 =

761 - 628 =

432 - 259 =

You should be able to answer each one within 4 seconds to be considered good.

So does anyone have some good methods in their head for this? I can rarely work that fast in my head. Of course if its 430-225 its a lot easier but it's not always that simple.

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# Mental Subtraction

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