In an army selection process, the ratio of selected to unselected was 6:1. If 90 less had applied and 30 less selected, the ratio of selected to unselected would have been 8:1. How many candidates had applied for the process?

Let $$7x$$ candidates applied for the process.

Candidates selected = $$6x$$ and candidates not selected = $$x$$

If candidates applied = $$7x - 90$$

Candidates selected = $$6x - 30$$

=> Candidates not selected = $$(7x - 90) - (6x - 30) = x - 60$$

According to ques,

=> $$\frac{6x - 30}{x - 60} = \frac{8}{1}$$

=> $$6x - 30 = 8x - 480$$

=> $$2x = 480 - 30 = 450$$

=> $$x = \frac{450}{2} = 225$$

$$\therefore$$ Number of candidates who applied for the process = $$7 \times 225 = 1575$$