A salt and water mixture, of which 7.5% is salt, costs ₹22.50 per litre. Another salt and water mixture, of which 17.5% is salt, costs ₹z per litre. If the cost of twelve litres of a salt and water mixture, of which 22.5% is salt, is ₹450, find the value of z.

Correct option is A

1             :               2

cost of 1 litre = $$\frac{450}{12}$$ = 37.5​

Price of mixture 2 = $$\frac{22.5 + (2 \times 37.5)}{3}$$ = 32.5 Rs./ litre

Thus, the correct option is (a)

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