Let:
x= quarters
y= dimes
x+y=67
and
.25x+.10y=12.40
x=67-y
.25(67-y)+.10y=12.40
16.75-.25y+10y=12.40
16.75-.15y=12.40
Lets rearrange this:
-.15y+16.75=12.40
-16.75 -16.75
-.15y=-4.35
the negatives cancel out
.<u>15y</u>=<u>4.35
</u>.15<em /><em> <u /></em>.15
y=29
Back to the original x=67-y
x=67-29
x=38
So,
x=38
y=29
<em />
Given:

To find:

Solution:

Solving the equation (i):

Putting the value of x into the equation (ii):

Putting the value of y into the equation (i):

So, the value of 
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Complete question:
A project is graded on a scale of 1 to 5. If the random variable, X, is the project grade, what is the mean of the probability
distribution below?
Grade(X)_____ 1_____2_____3_____4_____5
Frequency____3 _____5____ 9 ____ 5 ____ 3
P(X) : _______ 0.1 ___0.2 ___0.4 ___ 0.2 __0.1
Answer:
3
Step-by-step explanation:
Given the probability distribution :
Grade(X)_____ 1_____2_____3_____4_____5
Frequency____3 _____5____ 9 ____ 5 ____ 3
P(X) : _______ 0.1 ___0.2 ___0.4 ___ 0.2 __0.1
The mean of the distribution :
Σ(X * P(X)) :
(1*0. 1) + (2 * 0.2) + (3 * 0.4) + (4 * 0.2) + (5 * 0.1)
0.1 + 0.4 + 1.2 + 0.8 + 0.5
= 3
Answer:
D'accord. Ainsi, la flèche ou le pointeur doit pointer dessus. Si ne pointe pas, que. Découvrez-le
Lol Ngolo Kante
I can see u re a Chelsea fan