Answer:
62.5%
Step-by-step explanation:
Answer:
0.173 probability that she gets exactly three questions correct.
Step-by-step explanation:
For each question, there are only two possible outcomes. Either she guesses the correct answer, or she does not. The probability of guessing the correct answer for a question is independent of other questions. So we use the binomial probability distribution to solve this question.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinations of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
Seven questions:
This means that 
Each question has four choices.
Abby guesses, which means that 
Find the probability to the nearest thousandth, that Abby gets exactly three questions correct.
This is P(X = 3).


Dave pays $15 and tax is $1.2 so dave spent a total of $16.20.
Mel pays $20 and tax is $1.6 so Mel spent a total of $21.60.
All you need to do is convert the percent to a decimal, so take 8 and divide by 100 and you get 0.08. then you need to multiply the cost by the tax so 15*0.08=1.2 then you just add tax to original amount 15+1.2=16.2
:)
Answer:
3/4 - 5/12
Step-by-step explanation:
first you make the demoninators the same so 3*4=12
and if you *3 you do it to the numerator
so its 9/12-5/12
the unsimplified fraction is 4/12
if wanted simplified version its 1/3