Five people want a photographer to take pictures of every possible group of three of them.
How many different photos will the photographer need to take?:confused:

C(5,3)

Five people want a photographer to take pictures of every possible group of three of them. How many pictures will the photographer need to take?

This is not a riddle. It is just wanting to know how many ways you can choose 3 items from 5.

C(5,3)=\frac{5!}{3!(5-3)!}

Do you know this notation? Factorials ans so forth. Do you have a calculator? Most of them will quickly do it.

You can do it yourself by going through all the combinations logically too, the answer is not large!

This is not a riddle. It is just wanting to know how many ways you can choose 3 items from 5.

C(5,3)=\frac{5!}{3!(5-3)!}

can you show me how to do this step by step?:confused:

you can do it yourself by going through all the combinations logically too, the answer is not large!

I still don't understand can you show me step by step please!:confused:

5! = 5x4x3x2x1, so expanding galactus' answer:

C(5,3) = \frac{5*4*3*2*1}{3*2*1*2*1}

5! = 5x4x3x2x1, so expanding galactus' answer:

C(5,3) = \frac{5*4*3*2*1}{3*2*1*2*1}

is the answer a total of 10:confused:

Yes

yes thank tou:)

You can also check by working out all the possible combinations yourself:

The first is obviously

123

Then you change the last digit until you run out

124
125

Now you change the 2nd digit and repeat

134
135

And again

145

Now you've run out of second digits so change the first:

234
235

Now change the second digit again:

245

Now the first again

345

Now we've found them all! Count them up and there's 10 :)

thank tou:)thank you, you have been of great help! :)