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

[Q]: Problem: in how many no . between 10 and 30 exactly two of the digits is 2 ?
[A]: 1


[Q]: Problem: a and b together can complete work in 6 days . a alone starts working and leaves it after working for 4 days completing only half of the work . in how many days it can be completed if the remaining job is undertaken by b ?
[A]: 12


[Q]: Problem: a train speeds past a pole in 15 seconds and a platform 100 m long in 30 seconds . its length is ?
[A]:
200 m