In a college the ratio of boys to girls is 31:23 . When 75 more girls join the college this ratio becomes 124:107. How many more girls shd join the college to make the number of boys and girls equal ?
a.75 b.90 c.60 d.85 e.none

• 31x / (23x+75) = 124/107
  3317x=2852x+9300
  465x=9300
  x=20
  ratio will be 620:460
  when 75 more girls join in a college
  620:460+75 = 620:535
  Diff b/w boys & girls = 85
  
  85 more girls to join in a college...
• 9 years agoHelpfull: Yes(1) No(0)
• (31:23)*4 = 124:92......make boys equal to new ratio 124:107
  124:92
  124:107
  
  107-92 = 15
  124-107 = 17
  
  15=75
  17=85
• 7 years agoHelpfull: Yes(1) No(0)