Answer:
Mean of the data set in the dot plot would be: 3.6
Step-by-step explanation:
As we know that Mean from the dot plot can be obtained by:
- adding the numbers and then
- divide the resulting sum by the number of addends.
Please check the attached figure where the dot plot is also plotted.
From the dot plot, it is clear that
There are 3 dots at 1.
There are 4 dots at 2.
There are 3 dots at 3.
There are 4 dots at 4.
There are 5 dots at 5.
There are 3 dots at 6.
All we have to do is to add the dots and divide the sum by the number of addend dots.
In other words:
There are 3 dots at 1 ⇒ 1+1+1
There are 4 dots at 2 ⇒ 2+2+2+2
There are 3 dots at 3 ⇒ 3+3+3
There are 4 dots at 4 ⇒ 4+4+4+4
There are 5 dots at 5 ⇒ 5+5+5+5+5
There are 3 dots at 6 ⇒ 6+6+6
As there are total 22 dots.
And the sum of all the dots with respect to their plot number = 79
i.e. 1+1+1+2+2+2+2+3+3+3+4+4+4+4+5+5+5+5+5+6+6+6 = 79
Thus
Mean of the data set in the dot plot = 79/22
= 3.6
Therefore, Mean of the data set in the dot plot would be: 3.6
120 = 15% x
15% = 0.15
x = 120 / 0.15 = 800
Because then you can replace the variables with the actual value and see of the equation is true.
-25 15/19 + 9/1
get a common denominator of 19
they multiplied 9/1 * 19/19 = 171/19
-25 15/19 + 171/19 =
change the mixed number to an improper fraction
(19* 25 +15)/19 = 490/19
-490/19 + 171/19 =
add together
-319/19
now convert the improper fraction back to a mixed number
19* 16 =304 319-304=15
-319/19 =-16 15/19
Answer:
There are 24 nickels
Step-by-step explanation:
Let x represent the number of nickels
Let y represent the number of quarters
—————————————————————
Value Value
Type Number of of
of of each all
Coin Coin Coin Coin
—————————————————————
Nickels | x | $0.05 | $0.05x
Quarters | y | $0.25 | $0.25y
—————————————————————
Totals 28 ——— $2.20
•••••••••••••••••••••••••••••••••••••••••••••••••
The first equation comes from the “Number of coins” column.
(Number of nickels) + (Number of quarters) = (total number of coins)
Equation: x + y = 28
—————————————————————
The second equation comes from the “value of all coins” column.
(Value of all nickels) + (Value of all quarters) = (Total value of all coins)
0.05x + 0.25y = 2.20
Remove the decimals by multiplying each term by 100:
5x + 25y = 220
—————————————————————
So we have the system of equations:
{x + y = 28
{5x + 25y = 202
Solve by substitution. Solve the first equation for y:
x + y = 28
y = 28 - x
Substitute (28 - x) for y in 5x + 25y = 220
5x + 25 (28 - x) = 220
5x + 700 - 25x = 220
-20x + 700 = 220
-20x = -480
x = 24
The number of nickels is 24.
————————————————————
Substitute in y = 28 - x
y = 28 - (24)
y = 4
The number of quarters is 4.
————————————————————
Checking:
24 nickels is $1.20 and 4 quarters is $1.00
That’s 28 coins.
Indeed $1.20 + $1.00 = $2.20
————————————————————
