Shanti has enough money to buy 90 pumps worth Rs 500 each. How many pumps can he buy, if he gets a discount of Rs 50 on each pump.

So cost of 90 pump = $90\times 500$ = Rs.45000

So total money that Shanti had = Rs.45000

Discount on each pump = Rs.50

So cost of each pump after discount = Rs.500 - Rs.50 = Rs.450

So, number of pumps in Rs.45000 = $\frac{45000}{450}$ = 10

Therefore Shanti can buy 10 pumps.

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