What will come in place of the question mark (?) in each of the following series?

15     21    33    51     75    (?) 

What will come in place of the question mark (?) in each of the following series?

15     19    83   119     631     (?)

What will come in place of the question mark (?) in each of the following series?

15     18    16   19     17    20    ?

What will come in place of the question mark (?) in each of the following series?

 15     12    17  10     ?    8    21     6 

What will come in place of the question mark (?) in each of the following series?

15     ?    24    33     97    122     

Direction: A shopkeeper has some kg. rice of same price. He sold 150 kg. rice at 25 Rs. per kg. and earned a profit of 25%, another 180 kg. rice is sold at a profit of 20% and rest are sold at a loss of 10%. If the shopkeeper earns Rs. 1230 profit on all the rice that he has sold then answers the following question:

If the shopkeeper sells his all rice at a profit of 20%, find the new profit. 

Direction: A shopkeeper has some kg. rice of same price. He sold 150 kg. rice at 25 Rs. per kg. and earned a profit of 25%, another 180 kg. rice is sold at a profit of 20% and rest are sold at a loss of 10%. If the shopkeeper earns Rs. 1230 profit on all the rice that he has sold then answers the following question:

If the shopkeeper earns 10% profit instead of 10% loss on the rest rice then find the difference between the old and new profit. 

Direction: A shopkeeper has some kg. rice of same price. He sold 150 kg. rice at 25 Rs. per kg. and earned a profit of 25%, another 180 kg. rice is sold at a profit of 20% and rest are sold at a loss of 10%. If the shopkeeper earns Rs. 1230 profit on all the rice that he has sold then answers the following question:

What is the total quantity of rice that the shopkeeper has?