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ഒരു ക്ലാസിലാകെ 550 വിദ്യാർഥികളുണ്ട്. ആൺകുട്ടികളുടെയും പെൺകുട്ടികളുടെയും അനുപാതം 6 : 5 ആണ്. അനുപാതം 5 : 6 ആക്കുന്നതിനായി എത്ര പെൺകുട്ടികളെ കൂടി ചേർക്കേണ്ടതുണ്ട്?

A60

B80

C90

D110

Answer:

D. 110

Read Explanation:

ആൺകുട്ടികളുടെ എണ്ണം = 550 × (6/11) = 300 പെൺകുട്ടികളുടെ എണ്ണം = 550 × (5/11) = 250 ക്ലാസിലേക്ക് ചേർക്കുന്ന പെൺകുട്ടികളുടെ എണ്ണം x എന്ന് കരുതുക. 300/(250 + x) = 5 : 6 ⇒ 250 + x = 300 × (6/5) ⇒ 250 + x = 360 ⇒ x = 360 - 250 = 110


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