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

Problem: a bag contains 12 red marbles . if someone were to remove 2 marbles from the bag , one at a time , and replace the first marble after it was removed , the probability that neither marble would be red is 25 / 36 . how many marbles are in the bag ?
48

Problem: working together , wayne and his son can shovel the entire driveway in three hours . if wayne can shovel six times as fast as his son can , how many hours would it take for his son to shovel the entire driveway on his own ?
7

Problem: in a forest 150 deer were caught , tagged with electronic markers , then released . a week later , 50 deer were captured in the same forest . of these 50 deer , it was found that 10 had been tagged with the electronic markers . if the percentage of tagged deer in the second sample approximates the percentage of tagged deer in the forest , and if no deer had either left or entered the forest over the preceding week , what is the approximate number of deer in the forest ?

3,000