Ritika purchased 'x' kg wheat at Rs. 30/kg and sold 8 kg of this at Rs. 'x' per kg and remain inng at Rs. 45/kg. Overall profit percent earned is 10%, then what quantity of wheat Ritika at rs. 45/kg ?

10 kg 

We have,

Cost price of wheat = Rs. 30 per kg

Selling price of 8 kg = Rs. x per kg

Selling price of remaining wheat = Rs. 45 per kg

Overall profit percentage = 10%

According to the question,

Cost price = Rs. 30 per kg

Total cost price = CP = Rs. 30 × x = 30x

Profit must be 10%

So, SP = 30x × 110/100 = 33x

For the first 8 kg of wheat, the selling price is Rs. 'x' per kg.

Selling price of 8 kg = 8 × x = 8x

For the remaining wheat, the selling price is Rs. 45 per kg.

Remaining quantity = (x - 8) Kg

According to the question

33x = 8x + (x - 8)45

33x = 8x + 45x - 8 × 45

x = 18 kg.

Quantity of wheat sold at Rs. 45 per kg = (x - 8) = 18 - 8 = 10 kg