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:
Step-by-step explanation:
we know that
The simple interest formula is equal to
where
A is the Final Investment Value
P is the Principal amount of money to be invested
r is the rate of interest
t is Number of Time Periods
in this problem we have
The inequality that represented this situation is
substitute the values and solve for t
![t \leq [(7,020/4,500)-1]/0.03](https://tex.z-dn.net/?f=t%20%5Cleq%20%5B%287%2C020%2F4%2C500%29-1%5D%2F0.03)
If George's driveway is a rectangle 12.2 m by 3.0 m, its dimensions in cm are
... 1220 cm long × 300 cm wide × 2 cm deep
Thus the volume of gravel required is
... (1220 × 300 × 2) cm³ = 732,000 cm³
George needs about 0.732 bags, so he will probably need to buy 1 bag.
