Surds And Indices Q35

35.	(25)7.5 x (5)2.5 ÷ (125)1.5 = 5?
	A. 8.5 B. 13 C. 16 D. 17.5 E. None of these

Answer: Option B

Explanation:

Let (25)^7.5 x (5)^2.5 ÷ (125)^1.5 = 5^x.

Then,	(52)7.5 x (5)2.5	= 5x
	(53)1.5

	5(2 x 7.5) x 52.5	= 5x
	5(3 x 1.5)

	515 x 52.5	= 5x
	54.5

 5^x = 5^{(15 + 2.5 - 4.5)}

 5^x = 5¹³

 x = 13.