SOLUTION: I have 30 coins consisting of 5 cent and 20 cent coins. If the total value of these coins is 4.05$, how many 5 cent coins do I have? I tried making a table, didn't work for me.

Question 1059246: I have 30 coins consisting of 5 cent and 20 cent coins. If the total value of these coins is 4.05$, how many 5 cent coins do I have?
I tried making a table, didn't work for me.
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
I don't use tables, but here's how I do it:
Let = number of 5 cent coins
Let = number of 20 cent coins
--------------------------------------
(1)
(2) ( in cents )
------------------------
Multiply both sides of (1) by
and subtract (1) from (2)
(2)
(1)
--------------------------

and
(1)
(1)
(1)
--------------------
You have 13 5 cent coins
You have 17 20 cent coins
---------------------------
check:
(2)
(2)
(2)
(2)
OK
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