This problem is a combination of the Poisson distribution and binomial distribution.
First, we need to find the probability of a single student sending less than 6 messages in a day, i.e.
P(X<6)=P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)+P(X=5)
=0.006738+0.033690+0.084224+0.140374+0.175467+0.175467
= 0.615961
For ALL 20 students to send less than 6 messages, the probability is
P=C(20,20)*0.615961^20*(1-0.615961)^0
=6.18101*10^(-5) or approximately
=0.00006181
Answer:
126.
Step-by-step explanation:
also, Rounded to 17.
Answer:
Equal to
Step-by-step explanation:
14/18 is just 7/9 but with the numerator and denominator multiplied by 2
Answer:
3/4°
Step-by-step explanation:
84+72+108+60+156= 480 people
480*x= 360°
x= 360°/480= 3/4°
Answer:
x^3 + 1/x^3 = 488
Step-by-step explanation:
- x^2 + 1/x^2 = 62
- x^2 + 1/x^2 + 2 = 64
- ( adding 2 in both sides )
- (x + 1/x ) ^2 = 64
- x + 1/x = 8
now,
- ( x+ 1/x ) ^ 3 = 512
- x^3 + 1/x^3 + 3 × x × 1/x ( x + 1/x )
- x^3 + 1/x^3 + 3 ( 8 )
- ( since x + 1/x = 8 )
- x^3 + 1/x^3 + 24 = 512
- x^3 + 1/x^3 = 488
hence, we got x^3 + 1/x^3 = 488