Answer:
0.2752512
Step-by-step explanation:
The formula you are looking for is the binomial probability:
n!
P (X) = ------------ * (P)^X * (q)^n - X
(n- X)! X!
For your particular problem:
n=7
X=2
q = 1-p = .8
7!/(5!*2!)*(.2)^2*(.8)^5 = 0.2752512
Hope this helps, have a nice day/night! :D
Answer: The age of the twins is 10 years.
Step-by-step explanation:
Suppose the age of older sister be x
Let the age of twins sister be x-9, as they are born after 9 years.
Product of their ages be

Sum of their ages will be

According to question,

So, Age of older sister will be 19 years.
Age of the twins will be

Hence, the age of the twins is 10 years.
Answer:
I believe the answer is 48 gallons.
Step-by-step explanation:
Multiply 1.6 by 30 and you get 48
the first solution is 20% acid, and say we'll be using "x" liters, so how many liters of just acid are in it? well 20% of "x" or namely 0.2x. Likewise for the 60% acid solution, if we had "y" liters of it, the amount of only acid in it is 0.6y.

