SCHOOL KK = 83300 × 65/35 × 32/100⇒ K = 49504From school LL = 101520 × 60/40 × 30/100⇒ L = 45684From school MM = 113520 × 40/60 × 30/100⇒ M = 22704From school NN = 60830 × 65/35 × 40/100⇒ N = 45188From school OO = 27000 × 55/45 × 25/100⇒ O = 8250⇒ TOTAL number of students present in the Biology examination from all the schools together = (49504 + 45684 + 22704 + 45188 + 8250) = 171330