Esther purchased two rock tumblers and one spy pen for $74. eli purchased two puzzles and a spy pen for $50. sabine purchased a rock tumbler and two puzzles for $57. based on this, how much does one puzzle cost?

The cost of one puzzle be $15 .

Step-by-step explanation:

Let us assume that the cost of rock tumblers be x.

Let us assume that the cost of spy pen be y.

Let us assume that the cost of puzzels be z.

Esther purchased two rock tumblers and one spy pen for $74.

Than the equation becomes

2x + y = 74

Eli purchased two puzzles  and a spy pen for $50.

Than the equation becomes

y + 2z = 50

Sabine purchased a rock tumbler and two puzzles for $57. Based

Than the equation becomes

x + 2z = 57

Than the three equation are

2x + y = 74

y + 2z = 50

x + 2z = 57

Subtracted y + 2z = 50 from 2x + y = 74 .

2x - y + y - 2z = 74 - 50

2x - 2z = 24

x - z = 12

Now using the equation x - z = 12 and x + 2z = 57  .

Subtracted  x - z = 12 from  x + 2z = 57  .

x - x + 2z + z = 57 - 12

3z = 45

z = 15

Therefore the cost of one puzzel be $15.

the correct answer is 5 6 and 7