A can do a job in 45 days and B can do it in 30 days. A and B working together will finish four times the amount of work in ------- days?
Choose the correct choice from the following choices.
A) 30days
B) 45 days
C) 80 days
D) 72 1/2 days
E) 72 days
1/45+ 1/30 = 5/90 = 1/18   18/1= 
<gadget id="calculator">18/1</gadget>
<output>18</output>
18*4= 
<gadget id="calculator">18*4</gadget>
<output>72</output>
72 days   Answer:72 days
<result>E</result>
A can do a job in 45 days and B can do it in 30 days. A and B working together will finish four times the amount of work in ------- days?