Answer:50
Step-by-step explanation: 50 because if the ratio of tomatoes to red apples is 2:5 and there are 20 tomatoes, they obviously somehow got from 2 to 20. they did this by multiplying 10, so just multipy 10 on the other side which gives you 5 times 10 which is 50. there are 20 tomatoes to 50 red apples :D