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jovy had coin in her mini bank that amounted to 45.50.
if she had 7 more 50-centavo coins than 1-peso coins in her bank,
how many 50-centavo coins and 1-peso coins had she collected?
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The problem does not say that there are only 50-centavo and 1-peso coins in the collection,
but we, as intelligent persons, do understand it . . . (even without explicit instructions, isn't it ?)
Temporarily, take 7 50-centavo coins from the collection, for a moment.
You will have same number of 50-centavo coins as the number of 1-peso coins,
and the total amount of the reduced collection will be 4550 - 7*50 = 4200 centavo.
Now, if "n" is the number of 50-centavo coins, then the number of the 1-peso coins is also n.
So, the total money equation in the reduced collection is
50n + 100n = 4200 centavo, or 150n = 4200, which gives n = = 28.
Thus we conclude that there are 28 1-peso coins in the collection and 28+7 = 35 50-centavo coins. ANSWER
CHECK. 28*100 + 35*50 = 4550 centavo, in total. ! Correct !
Solved. // Notice that it is, practically, a MENTAL solution.
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On coin problems, see the lessons
- Coin problems
- More Coin problems
- Solving coin problems without using equations
- Kevin and Randy Muise have a jar containing coins
- Typical coin problems from the archive
- Three methods for solving standard (typical) coin word problems
- More complicated coin problems
- Advanced coin problems
- Solving coin problems mentally by grouping without using equations
- Non-typical coin problems
- Santa Claus helps solving coin problem
- OVERVIEW of lessons on coin word problems
in this site.
You will find there the lessons for all levels - from introductory to advanced,
and for all methods used - from one equation to two equations and even without equations.
Read them and become an expert in solution of coin problems.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this online textbook under the topic "Coin problems".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.