Answer:
f^-1(x) = x + 4
Step-by-step explanation:
They are both equivalent to 1, so they are equal.
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
I: 2x+y=5
II:3x+2y=4
start by eliminating y
-2*I: -4x-2y=-10
II: 3x+2y=4
add both equations together
-2*I+II: -4x-2y+3x+2y=-10+4
-1x=-6
x=6
insert x=6 into I:
2*6+y=5
y=5-12
y=-7
so the solution is x=6, y=-7
