Answer:
Probability that one of them is mathematics and other two are either physics or history books = 0.51
Step-by-step explanation:
Given - A student needs to select 3 books from 3 different mathematics, 3 different physics and 1 history books.
To find - What is the probability one of them is mathematics and other two are either physics or history books ?
Solution -
Given that,
A student needs to select 3 books from 3 different mathematics, 3 different physics and 1 history books.
So,
Total number of books = 3 + 3 + 1 = 7
The student has to select 3 books
So, Total number of ways =
= 35
So,
Probability that one of them is mathematics and other two are either physics or history books is -
= 
= 
= 
= 0.51
⇒Probability that one of them is mathematics and other two are either physics or history books = 0.51
Answer: a slice of pizza cost $1.25 and a 12-ounce cola cost $0.50.
Step-by-step explanation:
Let slice of pizza cost x and a 12-ounce cola cost y.
Then Sara's order cost: 2x+y=3
and Sydney's order cost: 3x+2y=4.75
From the first equation we have: y=3-2x and put this to the second equation:
3x+2(3-2x)=4.75
3x+6-4x=4.75
x=1.25
y=3-1.25*2=0.50
Answer: a slice of pizza cost $1.25 and a 12-ounce cola cost $0.50.