SOLUTION: there are 300 marbles in a jar that contains only blue and red marbles. the number of blue marbles is 20 less than 4 times the number of red marbles. how many red marbles are in th

Question 676682: there are 300 marbles in a jar that contains only blue and red marbles. the number of blue marbles is 20 less than 4 times the number of red marbles. how many red marbles are in the jar?
Answer by rm29924(97) (Show Source): You can put this solution on YOUR website!
Let x = the number of red marbles
4x-20 = the number of blue marbles
x+4x-20=300
5x-20=300
add 20 to both sides
5x=320
divide both sides by 5
x=64
there are 64 red marbles in the jar
check answer by plugging it into the original equation
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