sarahlavello
sarahlavello sarahlavello
  • 24-04-2018
  • Mathematics
contestada

You have 12 CDs, but only have time to listen to two of them. How many combinations of CDs do you have to choose from?

Respuesta :

11beehshahbaz 11beehshahbaz
  • 24-04-2018
Total number of CDs = 12
Number of CDs that can be selected at once = 2

Selecting 2 CDs from 12 means combination of 12 objects taken 2 at a time. This can be calculated by 12C2.

[tex]12C2 = \frac{12!}{2!*(12-2)!} \\ \\ 12C2= \frac{12!}{2!*10!} \\ \\ 12C2= \frac{12*11}{2} \\ \\ 12C2=66[/tex]

This means, we have 66 possible combinations to choose from 
Answer Link

Otras preguntas

If 5 times the value of a number is increased by 3, the result is 28. What is the number?
Solve the following equations enter x-coordinate of the solution round to the nearest tenth 5y+2y=22 -2y+6y=3
A number decreased by negative three is equal to -40. Write an equation and find the number.
A car traveling in a straight line has a velocity of 5.0 m/s. After an acceleration of 0.75 m/s/s, the cars velocity is 8.0. In what time interval did the accel
Why will a decrease in pH of the stomach affect protein digestion? Decrease in pH of the stomach will distort the structure of peptides in food, which affects t
what was the Powhatan confederacy and how did the group interact with the British settlers
the two main types of fermentation are called what
31 divided by 2 0ver 4 times 2 equals
what is 5.50 x (20 + 18.50)?
Why did bacons rebellion collapse