Which situation involves combinations?

a. choosing 3 flavors of ice cream out of 15 for an ice cream sundae.

b. choosing first, second, and third place winners in a cooking contest.

c. choosing a club president, vice president, and treasurer out of 10 candidates.

d. choosing 3 out of 8 possible activities for the morning, afternoon, and evening.

 Option 'A' is correct.

Step-by-step explanation:

Combination means combination of k things from n objects without repetition irrespective of arrangement and order .

But Permutation means selection of objects in which order of the objects matters, i.e. in arrangement and in order too.

Here,

B) Choosing first, second, and third place winners in a cooking contest.

Definitely it needs an order or arrangement as the order of the position of winners matters as it is, so it is permutation not combination.

C) Choosing a club president, vice president, and treasurer out of 10 candidates.

Since there is a rank so, order of the rank matters too, so, it is a permutation too.

D) Choosing 3 out of 8 possible activities for the morning, afternoon, and evening.

Since it is talking about the sequence of activities to be done in morning , afternoon and evening, so the order matters here too.

But,

A) Choosing 3 flavors of ice cream out of 15 for an ice cream sundae.

In this case order does not matter,it asks for different flavor i.e. without repetition choosing 3 things from 15 objects.

Hence, Option 'A' is correct.

its c or d   take a lucky guess my dude

- "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."