Combinations

If the number of elements increases by 3, it increases the number of combinations of the second class of these elements five times. How many are the elements?

Correct answer:

n =  3

Step-by-step explanation:

C2(6)=(26)=2!(62)!6!=2165=15 5 (2n) = (2n+3) 5 n /2 5 n(n1)=(n+3) (n+2)  5 n(n1)=(n+3) (n+2) 4n210n6=0 4=22 10=25 6=23 GCD(4,10,6)=2  2n25n3=0  a=2;b=5;c=3 D=b24ac=5242(3)=49 D>0  n1,2=2ab±D=45±49 n1,2=45±7 n1,2=1.25±1.75 n1=3 n2=0.5 n>0 n=n1=3   Verifying Solution:  C1=(2n)=3 C2(3)=(23)=2!(32)!3!=13=3  C2=(2n+3)=(23+3)=15 n=3

Our quadratic equation calculator calculates it.




Did you find an error or inaccuracy? Feel free to write us. Thank you!







Tips for related online calculators
Are you looking for help with calculating roots of a quadratic equation?
Would you like to compute the count of combinations?
Do you have a linear equation or system of equations and looking for its solution? Or do you have a quadratic equation?

You need to know the following knowledge to solve this word math problem:

Related math problems and questions: