Andy and Jimmy collected 370 toy cars altogether. 1/4 of Andy's toy cars was 25 more than 1/5 of Jimmy's toy cars. How many toy cars did Andy collect than Jimmy?
+23246 Let A represent the number of toy cars that Andy has.
Let J represent the number of toy cars that Jimmy has.
Since the total number that Andy and Jimmy have is 370, we have this equation:
A + J = 370
"1/4 of Andy's toy cars" is written as " 1/4 · A "
"1/5 of Jimmy's toy cars" is written as " 1/5 · J "
"was 25 more than" is written as " = 25 + "
So we now have the equation: 1/4 A = 25 + 1/5 J.
To get rid of fractions from this equation, multiply the equation by 20:
20 [ 1/4A = 25 + 1/5 J ] ---> 5A = 500 + 4J
Rewriting this equation: 5A - 4J = 500
Putting these two equations together:
A + J = 370 ---> multiply by 4 ---> 4A + 4J = 1480
5A - 4J = 500 ---> 5A - 4J = 500
Adding down the columns: 9A = 1980
Dividing by 9: A = 220 (number of Andy's toy cars)
Since the total number of cars is 370, Jimmy has 150 toy cars.
+1639 Andy and Jimmy collected 370 toy cars altogether. 1/4 of Andy's toy cars was 25 more than 1/5 of Jimmy's toy cars. How many toy cars did Andy collect than Jimmy?
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A + J = 370
4(25 + J/5) + J = 370
J = 150
I'll let you figure out the rest. 
