Ques:- How often between 11 o’clock and 12 o’clock are the hands of a clock in integral number of minutes apart?
A. 54 times
B. 55 times
C. 56 times
D. 58 times
Ques:- Gold is 19 times as heavy as water and copper is 9 times. In what ratio should these metals be mixed so that the mixture may be 15 times as heavy as water?
A. 2 : 1
B. 3 : 2
C. 4 : 3
D. 5 : 4