Answer:
126
Step-by-step explanation:
Using the definition of n = n! / r ! (n - r) !
where n ! = n(n - 1)(n - 2) ........ × 3 × 2 × 1
9
= 9 ! / 4 ! 5 ! ← cancel 5 ! on numerator/ denominator
=
=
= 126
4 just count how many are there that are between 19-21
1;2;5 are the correct statements
Answer:
Is there supposed to be an attachment? if so please send it so I can answer your question.
Answer:
Si tienes la respuestas podrias ponerla :( tengo la misma clase