Mathematics Hack Part 5 of 5

In the last part of the mathematics hack, here's how you convert Deg F to Deg C and vice versa

(Image taken from the internet and credits belongs to their owner)

For mental calculation, using mutiples of 2 and adding 30 make things so much easier. 

Of course you have a calculator or phone with a calculator, you can get more accurate conversion by just adding / subtracting 32 and multiply / divide by 1.8.