Answer :
9
Explanation :
The expression above signifies the Permutation expression
Permutation expression is given as nPr
The Permutation expression is calculated as:
nPr = P(n, r) = n! / (n - r)!
It the above question, we were asked to evaluate the expression 9P1
From the above question, we can see that:
n = 9 and r = 1
Therefore, the expression
9P1 = 9! / ( 9 - 1) !
9P1 = 9! / 8!
= 9 × 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1 / 8 × 7 × 6 × 5 × 4 × 3 × 2 × 1
= 362880 /40320
= 9
Therefore, the evaluation of the expression 9P1 = 9
Z score = 66 - 76
---------- = - 1
10
from the tables of normal distribution this corresponds to 0.34-3 of the area under the normal curve
so reuired number od students = 0.3413 * 230 = 78
Answer:
B
Step-by-step explanation:
The solid circle at - 3 indicates that x can be equal to - 3
The arrow pointing left indicates the values of x are less than - 3
Then
x ≤ - 3 → B
divide 400 by 24
400 / 24 = 16.666
so they would need to buy 17 crates