how many odd integers from 1 to 50 ( both inclusive ) have odd number of factors ?
"integers having odd number of factors will be perfect squares . odd numbers will have odd perfect squares . thus , the possible values for the perfect squares are : 1,9 , 25,49 and the corresponding integers are 1,3 , 5,7 ( more than 3 ) . thus b is the correct answer ."
subtract(subtract(divide(divide(50, const_2), const_2), const_10), const_10)