Hello, you can prepare Aptitude from lots of sites. There are many free mock test providing sites. You can visit them to know how you perform.
Aptitude is needed in all the fields so you will get it easily. You can also visit India bix,examveda and many more sites for aptitude.
On the other half , you can solve books of Aptitude. RS Agarwal is one of the best for question bank.
Hope it helps!

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