The number of ways five children can pose for a photograph line up in a row is given by the number of permutations of 5 elements in 5 different positions (positions in the line), then

number of ways = number of permutations of 5 elements = 5! = 5 * 4 * 3 * 2 * 1 = 120

Since the first children that occupies the line can be on any of the positions (5 positions) , but then the second one can choose any of the 4 remaining positions (since the first children had already occupied one) , the third can choose 3 ... and so on.

5 0

3 years ago

A human heart beats an average of 80 beats per minute. How many beats is this in an hour?

Aleksandr [31]

Answer:

4800 beats an hour

Step-by-step explanation:

there are 60 minutes in and hour

the heart beats 80 times per minute( that is actually a very high heart rate)

80*60=4800 per hour

8 0

3 years ago