Answer:70
Step-by-step explanation:
Given
total of 7 friends need to be divided in two groups with 3 member each and 1 leader
leader can be chosen out of 7 person in [tex]^7C_1[/tex] ways
And 3 person out of remaining 6 persons in [tex]^6C_3[/tex] ways
thus a total of [tex] ^7C_1\times ^6C_3[/tex] ways is possible
If order is not matter then
[tex]\frac{140}{2} [/tex] ways are possible