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":
Answer:
r = 
Step-by-step explanation:
We simply are rearranging C= 2πr in terms of <em>r</em>. We just divide 2π on both sides.
Answer: only C and E
Step-by-step explanation:
Answer:
Quedan 153 sillas
Step-by-step explanation:
Primero sabemos que en una sala de teatro tenían 7 filas, y en cada una de esas filas habían 23 sillas.
Entonces, originalmente, el número total de sillas es 7 veces 23:
S = 7*23 = 161
Luego sabemos que quitan 8 de esas sillas, entonces el número de sillas que quedan es la diferencia entre el número original de sillas, 161, y 8, que nos da:
S = 161 - 8 = 153
Quedan 153 sillas
Answer:
Step-by-step explanation:
This line was never finished, so you finish it like this:
3 = −⅖ + b
Parallel Lines have SIMILAR <em>RATE OF CHANGES</em> [<em>SLOPES</em>], so ⅖ remains the way it is.
I am joyous to assist you anytime.
