The question is incomplete:
James has dimes and quarters saved up in his change jar. He has a total of 162 coins totaling $31.20 what is the total amount james has in quarters?
a. $10.00
b. $6.20
c.$15.50
d.$25.00
Answer:
d.$25.00
Step-by-step explanation:
With the information provided, you can write the following equations given that dimes are equal to 0.10 and quarters to 0.25 to determine the number of dimes and quarters that James has:
x+y=162 (1)
0.10x+0.25y=31.20 (2), where:
x is the number of dimes
y is the number of quarters
First, you can solve for x in (1):
x=162-y (3)
Then, you have to replace (3) in (2) and solve for y:
0.10(162-y)+0.25y=31.20
16.2-0.10y+0.25y=31.20
0.15y=31.20-16.2
0.15y=15
y=15/0.15
y=100
Finally, you have to replace the value of y in (3) to find x:
x=162-100
x=62
Now, you know that James has 100 quarters and you can multiply this number for the value of a quarter to find the amount James has in quarters:
100*0.25=25
According to this, the answer is that James has $25 in quarters.
Answer:
<em>Thus, the dimensions of the metal plate are 10 dm and 8 dm.</em>
Step-by-step explanation:
For a quadratic equation:
The sum of the roots is -b and the product is c. Note the leading coefficient is 1.
We know the perimeter of the rectangular metal plate is 36 dm and its area is 80 dm^2. Being L and W its dimensions, then:
P=2(L+W)=36
A=L.W=80
Note both formulas are closely related to the roots of the quadratic equation, we only need to adjust the data for the perimeter to be exactly the sum of L+W and not double of it.
Thus we use the semi perimeter instead as P/2=L+W=18
The quadratic equation is, then:
Factoring by finding two numbers that add up to 18 and have a product of 80:
The solutions to the equation are:
x=10, x=8
Thus, the dimensions of the metal plate are 10 dm and 8 dm.
Answer:
C
Step-by-step explanation:
The rate of charge is how often you are charged something. If x represents miles than every ? miles you are charged 2.5. The 3 at the end is the y intercept or the point where you start so no matter how many miles you go you automatically owe 3 dollars
