Three bells ring together and they will ring at intervals of $6$ seconds,$7$ seconds and $8$ seconds respectively. After what interval will they again ring together? (in seconds)

The $LCM$ of $2^{2} \times 3^{2} \times 5 \times 11$,$2^{4} \times 3^{4} \times 5^{2} \times 7$,and $2^{5} \times 3^{3} \times 5^{2} \times 7^{2} \times 11$ is:

$L.C.M.$ and $H.C.F.$ of two numbers $x$ and $y$ are $315$ and $3,$ respectively. If $x+y=36,$ the value of $\frac{1}{x}+\frac{1}{y}$ is

What is the least number of cut pieces of equal length that can be cut out of two lengths $10\, m\, 857\, mm$ and $15\, m\, 87\, mm$?

Find the greatest number which will divide $25, 73$ and $97$ so as to leave the same remainder in each case.

Two pipes of length $1.5\, m$ and $1.2\, m$ are to be cut into equal pieces without leaving any extra length of pipes. The greatest length of the pipe pieces of same size which can be cut from these two lengths will be (in $metre$)