A bag contains only apple and oranges. The probability an apple is picked randomly is 1 in 5. The apple is returned, and five more apples are added to the bag. The probability of an apple being picked is now 1in 3. How many apples were there originally?

2 simultaneous unknown equations. Let x be the number of apples originally, and n the number of fruits in the bag in total originally. i) first scenario, where probability is 1/5, x/n = 1/5    5x= n  ii) second scenario, where 5 apples where added. (x+5)/(n+5)=1/3 3x+15= n+5present them as one equation: i) +5 on the n side---> 5x+5=n+5. Now can it can be presented as: 5x+5= 3x+15. solve the equation:5x-3x=15-5; 2x=10x=5. Therefore, there were 5 apple originally in the bag.