I have 30 coins consisting of 5c coins and 20c coins. The total value of the coins is $3.45. How many of each kind do I have?
some hellp please!
number of 5 c coins --- x
number of 20 c coins ---- y
x + y = 30
5x + 20y = 345
or x + 4y = 69
subtract: 3y = 39
y = 13
then x = 17
state your conclusion.
Well, the answer is 17 however it is still possible to be a different answer depending on the question
To solve this problem, you can use a system of equations. Let's assume that you have x number of 5c coins and y number of 20c coins.
1) The total number of coins is 30:
x + y = 30
2) The total value of the coins is $3.45:
0.05x + 0.20y = 3.45
Now we can solve this system of equations. There are different ways to solve it, but let's use the method of substitution:
1) Solve the first equation for x:
x = 30 - y
2) Substitute x in the second equation:
0.05(30 - y) + 0.20y = 3.45
3) Simplify and solve for y:
1.5 - 0.05y + 0.20y = 3.45
0.15y = 1.95
y = 13
4) Substitute y back into the first equation to find x:
x + 13 = 30
x = 30 - 13
x = 17
Therefore, you have 17 of the 5c coins and 13 of the 20c coins.
To solve this problem, you can use a system of equations. Let's say the number of 5c coins is 'x' and the number of 20c coins is 'y'. We can set up two equations based on the given information.
1) The total number of coins is 30: x + y = 30.
2) The total value of the coins is $3.45: 0.05x + 0.20y = 3.45.
Now, we need to solve these equations simultaneously to find the values of 'x' and 'y'. There are different methods to solve a system of equations, but I'll use the substitution method.
Let's solve the first equation for 'x' in terms of 'y': x = 30 - y.
Substitute this expression for 'x' into the second equation:
0.05(30 - y) + 0.20y = 3.45.
Now, you can simplify and solve for 'y':
1.5 - 0.05y + 0.20y = 3.45.
Combine like terms:
0.15y = 1.95.
Divide both sides by 0.15 to isolate 'y':
y = 1.95 / 0.15.
y ≈ 13.
Now, substitute the value of 'y' back into the first equation to find 'x':
x + 13 = 30.
x = 30 - 13.
x = 17.
Therefore, you have 17 5c coins and 13 20c coins.