A room is 12 ¼ m long and 7w wide. The maximum length of a square tile to fill the floor of the room with whole number of it’s tiles should be_________?

A. 93
B. 39
C. 75
D. 48
E. Either (a) or (b)
Explanation:
Let the two-digit number be 10a + b
a + b = 12 — (1)
If a>b, a – b = 6
If b>a, b – a = 6
If a – b = 6, adding it to equation (1), we get
2a = 18 => a =9
so b = 12 – a = 3
Number would be 93.
if b – a = 6, adding it to the equation (1), we get
2b = 18 => b = 9
a = 12 – b = 3.
Number would be 39.
There fore, Number would be 39 or 93.

A. 2/3
B. 3/5
C. 4/7
D. 5/9
E. None of these
Let the numerator and denominator of the fraction be ‘n’ and ‘d’ respectively.
d = 2n – 1
(n + 1)/(d + 1) = 3/5
5n + 5 = 3d + 3
5n + 5 = 3(2n – 1) + 3 => n = 5
d = 2n – 1 => d = 9
Hence the fraction is : 5/9.