Текст песни one direction - Math Question

You're insecure, so half of four,
Your old brains are not what they were before,
Add two threes, it's fine for us,
'cause we're young and we can still remember stuff

Everyone else can multiply by 60,
Everyone else can add two

Now take off one hundred and add on 24,
Then divide by two and add on seven more
And if you're struggling now it's not hard to tell
You don't know, your maths skills are terrible

If only you had a mind like me
You'd understand how to divide the sum by three,
And then just add on the age of this OAP
You don't know, your maths skills are terrible

It's really kinda pitiful