Answer:
122
Step-by-step explanation:
12 times 2 times 5 plus 2 gets rewritten as
(12)(2)(5) + 2
Follow PEMDAS and do multiplication first. From left to right...
24(5) + 2 { (12)(2) = 24 }
120 + 2 { (24)(5) = 120 }
122 { 120 + 2 = 122 }
The Lewis family and the Perry family each used their sprinklers last summer. The water output rate for the Lewis family's sprinkler was 15 L per hour. The water output rate for the Perry family's sprinkler was 40 L per hour. The families used their sprinklers for a combined total of 65 hours, resulting in a total water output of 1850 L . How long was each sprinkler used
Answer:
Hours of use of sprinkler by Lewis family is 30 hours.
Hours of use of sprinkler by Perry family is 35 hours.
Step-by-step explanation:
Let W = hours of use by Lewis family
65 - W = hours of use by Perry family
Then;
15W + 40*(65 - W) = 1850
15W + 2600 - 40W = 1850
(15 - 40)W = 1850 - 2600
-25W = −750
W = 750/25 = 30
Therefore;
W = 30
65 - W = 65 - 30 = 35
Hence,
Hours of use by Lewis family is 30 hours.
Hours of use by Perry family is 35 hours.
(x,y) so you start at the orgin and go down two because it's negative. then you go right six and plot your point.
negative number - down or left
positive number - up or right
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 mean is 2.5. also there is mean, median, mode calculators online to help you with these in the future