Problem number 18. Two identical trains, each with 31 cars, are traveling in opposite directions. When car number 19 of one train is opposite car number 19 of the other, which car is opposite car number 12? A, 7. B, 12. C, 21. D, 26. E, 31. Notice that the cars are numbered going in opposite directions. So for a stop car, if we're at car 19, the next one would be 20, and 21, and so on. But for the bottom car, if we have car 19 here, car 20 would be on the left side, then car 21, and so on, all the way to 31. We can figure out where car 12 is on either train and go from there. So you imagine this top train, you get to car 12. There's a difference of seven cars from 19 to 12, because 19 minus 12 is 7. So on this side, we will have to add 7 to 19 to figure out the car number that faces car number 12. 19 plus 7 is 26. So on the other train, the car number is 26. So the answer is D, 26.

trains

car numbers

opposite directions

problem solving

math logic