Mathematic question?

Question

There were 210 children at the swimming pool complex, 1/5 of the boys and 3/8 of the girls were swimming. If there were 63 pupils swimming in the pool,  how many girls were there swimming in the pool?

Answer

1/5B + 3/8G = 63
B+G =210

8B + 15G =2520
8B + 8G  = 1680

7G  = 840

g=120

Number of girls swimming = 360/8 = 45

Answer

210 people. 1/5 were boys(42).. that leaves 168 girls 3/8 of the 168 girls were swimming so thats 63. The fact of 63 pupils... well all girls..  ;)

Answer

Take Girls g, Boys b
Now Girls= 3*g/8
         Boys= 1*b/5

Total b+g= 210 => b=210-g

Put value of b in below equation:

=> 63= (3*g/8) +(b/5)
=>63 = (3*g/8) + (210-g/5)
=> g=120

Girls= 3*g/8= 3*120/8= 360/8 = 45

  So 45 girls were swimming there.

Mathematic question?

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