00:01
Question number one, we're asked how many different ways can you have first, second, third, and fourth in a race with 10 runners? so what you need to do is write down or draw four lines, and this is to signify first place, second place, third place, fourth place.
00:19
Okay, so in a race with 10 racers, there are 10 possible choices for us to have someone in first place.
00:28
And then once that person is in first place, now there are 9.
00:31
People left that could potentially be in second place.
00:36
And then that will be eight people left with a third place and seven people left with the fourth place.
00:41
So we multiply the choices together.
00:43
So that's 10 times nine times eight times seven.
00:46
So which means we will have a total of 5 ,000 and 40 different combinations.
00:52
So the answer is d.
00:55
Question number two, how many different combinations of management can there be to fill the positions of manager? so that's one secretary and advisor.
01:08
So we have three positions that needs filling.
01:11
And there are 12 eligible candidates.
01:13
So similar to question one, we would have 12 choices for manager, which means we're left with 11 choices for secretary and 10 choices for advisor.
01:25
So this is 12 times 11 times 10, which works out to be 1 ,320.
01:33
So that is option h.
01:38
Number three, how many different words can we make using s -h -a -l, assuming every combination possible is a word? so we have four letters and four spots, which means four choices times three times two times one.
01:55
Okay, so this is equal to 24, which is g.
01:59
Number four, robin has five pairs of shoes that match with six different pairs of socks.
02:08
So how many different pairings can he make? well, this one would just be six different choices for socks times five different possible choices for shoes.
02:20
So that would be 30...