Question

Say you've got a campaign that performs well on mobile devices with a max cpc bid of us$2. to show your ad to more customers on mobile devices, you increase your bid by 15% for searches on mobile devices. what would be the resulting bid for searches on mobile devices bid amount?

Answer 1

If you start with the bid of $2 dollars and increase it by 15% you end up with $2.3 bid after that. 

This calculation:

B = 2 + 2 x 0.15 = 2.3.

Businesses will often check to see how their campaigns are performing to make sure they are putting their advertising dollars into the right areas. It is important to make sure all marketing efforts are being put towards the areas where they can attract customers the most and have the largest return on investment of their spending. 

Answer 2

If you start with the bid of $2 dollars and increase it by 15% you end up with $2.3 bid after that. 
This calculation is pretty simple:
$B=2+2\cdot0.15=2.3$