SOLUTION: In Tae Kwon Do class, 40% of the students are boys. There are 18 fewer boys than girls. How many students are in the Tae Kwon Do class altogether?
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Question 1150617: In Tae Kwon Do class, 40% of the students are boys. There are 18 fewer boys than girls. How many students are in the Tae Kwon Do class altogether? Found 2 solutions by VFBundy, ikleyn:Answer by VFBundy(438) (Show Source):
You can put this solution on YOUR website! Number of girls = x
Number of boys = x - 18 = 0.4 = 0.4
Cross-multiply:
x - 18 = 0.4(2x - 18)
x - 18 = 0.8x - 7.2
0.2x = 10.8
x = 54
Number of girls = x = 54
Number of boys = x - 18 = 54 - 18 = 36
There are 54 girls in the class and 36 boys in the class. Therefore, there are 90 students in the class altogether.
Let x be the number of students in the class.
Then the number of girls is 0.6x, while the number of boys is 0.4x.
The difference is
0.6x - 0.4x = 18,
i.e.
0.2x = 18
x = 18/0.2 = 180/2 = 90. ANSWER