The task is to generate the correct answer for a given math problem.

[EX Q]: Problem: at a certain fruit stand , the price of each apple is 40 cents and the price of each orange is 60 cents . mary selects a total of 30 apples and oranges from the fruit stand , and the average ( arithmetic mean ) price of the 30 pieces of fruit is 56 cents . how many oranges must mary put back so that the average price of the pieces of fruit that she keeps is 52 cents ?
[EX A]: 1

[EX Q]: Problem: if a - b = 6 and a 2 + b 2 = 50 , find the value of ab .
[EX A]: a ) 7

[EX Q]: Problem: 70 is increased by 50 % . find the final number .
[EX A]:
105