What is the next number of the series? 50, 53, 46, 57,---------
কয়টি রেখার সাহায্যে একটি ত্রিভুজ আকা যায়?
There are 9 black and red stones of same size in a box. If you reach into the box with your eyes close, what is the minimum number of stones you must take out to be sure of having a pair that match?