Question

there are 2 father mother .but there are 3 children.Each have 2 father mother.how​

Answer 1

Answer:

A family consisting of one mother, one father, two daughters and a son is taking a road trip in a sedan. The sedan has two front seats and three back seats. If one of the parents must drive and the two daughters refuse to sit next to each other.

Answer 2

Step-by-step explanation:

Approach #1:

Sisters can sit separately in two ways:

1. one of them is on the front seat (2 ways). Others (including second sister) can be arranged in: 2 (drivers seat)*3! (arrangements of three on the back seat)=12 ways. Total for this case: 2*12=24

Or

2. both by the window on the back seat (2 ways). Others can be arranged in: 2 (drivers seat)*2 (front seat)*1(one left to sit between the sisters on the back seat)=4 ways. Total for this case: 2*4=8.

Total=24+8=32.

Approach #2:

Total # of arrangements:

Drivers seat: 2 (either mother or father);

Front seat: 4 (any of 4 family members left);

Back seat: 3! (arranging other 3 family members on the back seat);

So. total # of arrangements is 2*4*3!=48.

# of arrangements with sisters sitting together:

Sisters can sit together only on the back seat either by the left window or by the right window - 2, and either {S1,S2} or {S2,S1} - 2 --> 2*2=4;

Drivers seat: 2 (either mother or father);

Front seat: 2 (5 - 2 sisters on back seat - 1 driver = 2);

Back seat with sisters: 1 (the last family member left);

So, # of arrangements with sisters sitting together is 4*2*2*1=16.

48-16=32