Answer:
0.0656
Step-by-step explanation:
For each message, we have these following probabilities:
90% probability it is spam.
10% probability it is legitimate.
Compute the probability that the first legitimate e-mail she finds is the fifth message she checks:
The first four all spam, each with a 90% probability.
The fifth legitimate, with a 10% probability.

We need to perform multiplication and addition property for this problem to represent the final result in decimal form. So, the expression is,
9x100+2x10+3x0.1+7x0.001 .
Now 9 x 100= 900
2 x= 10= 20
3x0.1= 0.3
7x 0.001=0.007
Now we can all the numbers. Hence,
900+20+0.3+0.007=920.307
So, the decimal number is 930.307.
Answer:
−
7
i

Step-by-step explanation:
In order to get as many tickets they need 15 business class tickets and 12 economy class tickets (700x15=10,500)(375x12=4500) Which when you add those two makes 15,000.