Question

A question paper divided into two groups consisting of 3 and 4 questions respectively carries the note "it's not required to answer all the questions.One question must be answered from each group". In how many ways you can select the questions?
And Spamming not And:12. If you get this answer then don't post your answer pls...​

Answer 1

according to formula:

total no of ways to select questions

= (3-1)! (4-1)!

= 2! 3!

= 2 x 3 x 2

= 12 ............. ans..

explanation (2nd method).

you have to select at least one from each group.

so, from group 1, you can select either 1 or 2 or 3.

Total ways to select from group 1 = 3

similarly, from group 2, you can select 1 or 2 or 3 or 4.

Total ways to select from group 2 = 4

You have to do this selection in two parts(selection from group-1, selection from group-2)

so, required no of ways of selection = 3 x 4 = 12...

this is your answer.

Answer 2

Answer:

A B C

4 5 3

----------------------

2 2 1

4C base 2 × 5 C base 2 × 3 C base 1

6×10× 3 = 180