Answer:
7 tenths
Step-by-step explanation:
3 tenths + 4 tenths = 3/10 + 4/10 = 0.3 + 0.4 = 0.7
= 7 tenths
That it is 4,6090 because when u divide that ,400 by 2,400 u will get 4,000
Answer:
unreadable score = 35
Step-by-step explanation:
We are trying to find the score of one exam that is no longer readable, let's give that score the name "x". we can also give the addition of the rest of 9 readable s scores the letter "R".
There are two things we know, and for which we are going to create equations containing the unknowns "x", and "R":
1) The mean score of ALL exams (including the unreadable one) is 80
so the equation to represent this statement is:
mean of ALL exams = 80
By writing the mean of ALL scores (as the total of all scores added including "x") we can re-write the equation as:

since the mean is the addition of all values divided the total number of exams.
in a similar way we can write what the mean of just the readable exams is:
(notice that this time we don't include the grade x in the addition, and we divide by 9 instead of 10 because only 9 exams are being considered for this mean.
Based on the equation above, we can find what "R" is by multiplying both sides by 9:

Therefore we can now use this value of R in the very first equation we created, and solve for "x":

The values have being matched to the variables that they represent here:
- x-variable: the number of hours Sam works at the airport
- y variable: the amount in dollars that Sam has after paying back Daniel
- 12: amount in dollars that Sam earns per hour.
- 40: the amount in dollars Sam owes Daniel
<h3>How to solve for the equation.</h3>
The equation of this form y = 12x-40
The variable y has been said to be the amount sam has after Daniel has been paid.
X is the amount that has to be multiplied by what he earns in dollars by the hour.
40 dollars is the amount that he owes which is going to be subtracted from what he earns by the hour.
Read more on functions here:
brainly.com/question/17043948
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