What is the value of 10 C 2

Question

Matthew

Mathematics

5 July, 02:23

What is the value of 10 C 2

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Answers (1)

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Chain · Answer 1

The formula to use is the nCr combination formula

n C r = (n!) / (r! * (n-r) !)

where the exclamation marks indicate factorial notation

Plug n = 10 and r = 2 into the formula

n C r = (n!) / (r! * (n-r) !)

10 C 2 = (10!) / (2! * (10-2) !)

10 C 2 = (10!) / (2!*8!)

10 C 2 = (10*9*8!) / (2!*8!)

10 C 2 = (10*9) / (2!)

10 C 2 = (10*9) / (2*1)

10 C 2 = 90/2

10 C 2 = 45

Answer: 45