SOLUTION: 8 There are 50 boys and 60 girls in the cafeteria. After x boys and x – 5 girls have left the cafeteria, the probability of selecting a girl becomes 5/7 , what is the valu

Algebra ->  Numeric Fractions Calculators, Lesson and Practice -> SOLUTION: 8 There are 50 boys and 60 girls in the cafeteria. After x boys and x – 5 girls have left the cafeteria, the probability of selecting a girl becomes 5/7 , what is the valu      Log On


   

Question 1119195: 8 There are 50 boys and 60 girls in the cafeteria. After x boys and x – 5 girls have left the cafeteria, the
probability of selecting a girl becomes 5/7


, what is the value of x?
A) 30 B) 35
C) 40 D) 45
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!
+%2860-%28x-5%29%29+%2F+%28%2850-x%29+%2B+%2860-%28x-5%29%29%29+=+5%2F7+
++%2865-x%29+%2F+%28115-2x%29+=+5%2F7+
++%2865-x%29%2A7+=+%28115-2x%29%2A5+
++455-7x+=+575-10x+
+++++3x+=+120+
++x+=+highlight%28+40+%29+
——
Check: 50-40 = 10, 60-(40-5) = 25 , 25 / (10+25) = 25/35 = 5/7