For two weeks the school librarian recorded the number of library books returned each morning. The data are shown in the dot plo
t. The librarian found the mean number of books returned each morning.
DOT PLOT
0 has 2 dots 1 has 0 dots 2 has 0 dots 3 has 1 dot 4 has 0 dots
5 has 1 dots 6 has 2 dots 7 has 0 dots 8 has 2 dots 9 has 1 dot
10 has 1 dot 11 has 0 dots
LIBRARIANS WORK
8 + 6 + 10 + 5 + 9 + 8 + 3 + 6 55
------------------------------------------------- = ---- = 6.9
8 8
Is this the correct mean of this data set? If not, explain and correct this answer
DOT PLOT
0 has 2 dots 1 has 0 dots 2 has 0 dots 3 has 1 dot 4 has 0 dots
5 has 1 dots 6 has 2 dots 7 has 0 dots 8 has 2 dots 9 has 1 dot
10 has 1 dot 11 has 0 dots
LIBRARIANS WORK
8 + 6 + 10 + 5 + 9 + 8 + 3 + 6 55
------------------------------------------------- = ---- = 6.9
8 8
Is this the correct mean of this data set? If not, explain and correct this answer
1 answer:
You might be interested in
Answer:
The time taken by smaller pipe to fill the tank alone is 74.2 min
Step-by-step explanation:
Given as :
The time taken by two pipes to fill tank = 19 min
Let the time taken by larger pipe to fill tank = y
And the time taken by smaller pipe to fill tank = x
According to question
The smaller pipe takes 49 minutes longer than larger pipe
I.e x = y + 49
Now,
+
=
Or, +
=
Or, =
Or, 2 y + 49 =
Or, 19 × ( 2 y + 49 ) = y² + 49 y
Or, 38 y + 931 = y² + 49 y
Or, y² + 49 y - 38 y - 931 = 0
or, y² + 11 y - 931 = 0
Or, Applying quadratic equation method to calculate the value of y
so, y =
Or, y =
Or, y =
or, y =
or, y =
∴ y = 25.2 , - 36.5
So, The time taken by larger pipe = y = 25.2 min
and the time taken by smaller pipe to fill the tank = y + 49 = 25.2 + 49 = 74.2 min
Hence The time taken by smaller pipe to fill the tank alone is 74.2 min answer