A percentage problem

Can you help me solve this question?

Jayne is given £5 for her birthday.
She spends 30% of it.
How much of her birthday money does she spend?

And... Is my method correct for this question?
100-30=70
70/5=14
1.40

No, the asker's method is not correct. In fact, it looks to me like she is randomly doing operations with numbers...

To find 30% of something, one MENTAL MATH method that I like is to first find 10% of that something.

Now, 10% of something is of course 1/10 of it. And to find 1/10 of it, just divide that by 10.

So, we divide £5 by 10 to find 1/10 of £5. It is £0.50. That's 10% of the total. And 30% of the total is three times as much, or £1.50.

So Jayne spent £1.50.
See also this video that explains how to find percentages using mental math:

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