A fan of country music plans to make a custom CD with 14 of her 25 favorite songs. How many different combinations of 14 songs are possible? Is it practical to make a different CD for each possible combination?

4457400

Step-by-step explanation:

25C14 = 4457400

Not practical, these are too many

4,457,400  combinations.

Step-by-step explanation:

The number of combinations of 14 from 25 is a very large number :

25C14 =   25! / 14! 11!

=  4,457,400.

With so many possible combinations it would not be practical to make a Cd for all these possibilities.

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."