A is 1.5 times as fast as B. A alone can do the work in 30 days. If A and B working together in how many days will the work be completed?
Choose the correct choice from the following:	A) 23	B) 18	C) 21	D) 24	E) 25
A can finish 1 work in 30 days   18 can finish 1/1.5 work in 30 days - since A is 1.5 faster than 18   This means   18 can finish 1 work in 30*1.5= 
<gadget id="calculator">30*1.5</gadget>
<output>45</output>
45 days   Now using the awesome GMAT formula when two machines work together they can finish the job in= A18/ (A+18) = 45*30/(45+30) = 20*30/50 = 18 days   So answer is 18
<result>B</result>
A is 1.5 times as fast as B. A alone can do the work in 30 days. If A and B working together in how many days will the work be completed?