If Tk. 6,300 was invested in a share when the price per share was Tk. 9 and additional Tk. 4200 was invested in the same share when the price per share was Tk. 10, what was the average price per share?

Correct Answer: Tk. 9.375
a ও b দুটি ধনাত্মক সংখ্যা এবং ab/x = √a Or, x = ab/√a হলে x/√b = √(ab)