hi,
You have to use a formula which is known as of binomial coefficient which is :
k among n is : C ( n /k) = n! / k! ( n-k)!
! = factorial
ex : 5 object among 8 is : C ( 8/5 ) = 8 ! / 5! * ( 8-5) !
As 8! = 8*7*6*5*4*3*2*1 = 40 320
As 5! = 5*4*3*2*1 = 120
as 3 ! = 3*2*1 = 6
then : 40 320 / 120 * 6
40 320 / 720 = 56
Conclusion : there is 56 way to select 5 object among 8 of them.
ps : you can also use Pascal Triangle to do such a thing.
Answer:
4.4166666667 or 4.417
Step-by-step explanation:
7÷12-5=4.4166666667 or 4.417
Answer:
i think it would be 21 percent he got wrong so if he got 21 percent wrong it would be 79 percent right
Step-by-step explanation:
beacause if it was 10 question it would be 30 percent wrong since its 15 you divide it by 100 which would be 7 and 7 times 3 is 21
sorry if im wrong
you can round 15 to 20 and 8 and to 10
