SOLUTION: The cost of a pen is 30 cents more than the cost of a pencil. Jackson spent $4.30 when he bought five pens and two pencils. Can you calculate the individual cost of a pencil and pe

Algebra ->  Equations -> SOLUTION: The cost of a pen is 30 cents more than the cost of a pencil. Jackson spent $4.30 when he bought five pens and two pencils. Can you calculate the individual cost of a pencil and pe      Log On


   



Question 1088702: The cost of a pen is 30 cents more than the cost of a pencil. Jackson spent $4.30 when he bought five pens and two pencils. Can you calculate the individual cost of a pencil and pen?
Found 2 solutions by ikleyn, josmiceli:
Answer by ikleyn(52776) About Me  (Show Source):
You can put this solution on YOUR website!
.
pen = pencil + 30,   (1)

5 pens + 2 pencil = 430   (cents)

==========>

5*(pencil+30) + 2 pencil = 430,

5*pencil + 150 + 2 pencil = 430,

7 pencil = 430 - 150,

7 pencil = 280   ====>  pencil = 280%2F7 = 40 cents.


Answer. Pencil costs 40 cents.  Pen costs 40 + 30 = 70 cents.

Solved.



Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = the cost of a pencil ( in cents )
+x+%2B+30+ = the cost of a pen ( in cents )
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+5%2A%28+x+%2B+30+%29+%2B+2x+=+430+ ( in cents )
+5x+%2B+150+%2B+2x+=+430+
+7x+=+280+
+x+=+40+
and
+x+%2B+30+=+70+
A pen costs 70 cents
A pencil costs 40 cents
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check:
+5%2A%28+x+%2B+30+%29+%2B+2x+=+430+
+5%2A70+%2B+2%2A40+=+430+
+350+%2B+80+=+430+
+430+=+430+
OK