A can type 100 letters in 5 minutes. B and C typing together can type 50 letters in 2 minutes. If all of them are working together then they can type 90 letters in how many minutes?
1
4 minutes
2
3 minutes
3
2 minutes
4
5 minutes
5
None of these
A can type 100 letters in 5 minutes. B and C typing together can type 50 letters in 2 minutes. If all of them are working together then they can type 90 letters in how many minutes?