On selling 36 mobiles, a mobile vendor got a loss equivalent to the selling price of four mobiles. The loss percent is:

10%

Let the selling price of one mobile be Re. x

Then, the selling price of 36 mobiles is Rs. 36x

And the selling price of 4 mobiles is Rs. 4x

The loss of vendor = Rs. 4x

The cost price of the vendor = 36x + 4x = Rs. 40x

Loss% = \(\frac{4x}{40x}\)× 100

Loss% = 10%