How many paying stones, each measuring 2 1/2 m * 2 m are required to pave a rectangular court yard 30 m long and 16 1/2 m board? Choose the correct choice from the following:
A) 99	B) 87	C) 57	D) 54	E) 23
30 * 33/2 = 5/2 * 2 * x =&gt; x   = 99   99nswer:99
<result>A</result>
How many paying stones, each measuring 2 1/2 m * 2 m are required to pave a rectangular court yard 30 m long and 16 1/2 m board?