Anthony has been saving nickels (N), dimes (D), and quarters (Q) over the last year. He knows that he has twice as many nickels as quarters. When he takes the coins to the change machine to exchange them for paper money, he learns that he has 260 coins that total $29.75. Determine the number of each type of coin Anthony saved.

75 number of quarters

150 number of nickels

35 number of dimes

Step-by-step explanation:

Let x, y and z be the amount of quarters, nickel and dimes respectively.

he learns that he has 260 coins, thus;

x + y + z = 260 - - - (1)

Now, we are told that he has twice as many nickels as quarters.

Thus, number of nickels = 2x

y = 2x - - - (2)

From online research, we have the following cost;

1 quarter = $0.25

1 nickel = $0.05

1 dime = $0.1

Total cost is $29.75. Therefore;

0.25x + 0.05y + 0.1z = 29.75 - - - (3)

Put 2x for y in eq (1) and eq (3) to get;

x + 2x + z = 260

3x + z = 260 - - - (eq 4)

0.25x + 0.05(2x) + 0.1z = 29.75

0.25x + 0.10x + 0.1z = 29.75

0.35x + 0.1z = 29.75 - - - (eq 5)

From eq(4), z = 260 - 3x

Thus;

0.35x + 0.1(260 - 3x) = 29.75

0.35x + 26 - 0.3x = 29.75

0.05x = 29.75 - 26

0.05x = 3.75

x = 3.75/0.05

x = 75

So, z = 260 - 3(75)

z = 260 - 225

z = 35

Since y = 2x,

Then,y = 2(75) = 150

Thus,we have;

75 number of quarters

150 number of nickels

35 number of dimes

step-by-step explanation:

f

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions