subash can copy 50 pages in 10 hrs.subash and prakash together can copy 300 pages in 40 hours.in how much time prakash can copy 10 pages.
Choose the correct choice from the following:
A) 8
B) 10
C) 12
D) 4
E) 16
subhas 's 1 hr copy page=50/10= 
<gadget id="calculator">50/10</gadget>
<output>5</output>
5 page   (subhas+prakash)'s 1 hr copy page=300/40= 
<gadget id="calculator">300/40</gadget>
<output>15/2 = around 7.5</output>
7.5 page   from above prakash's 1 hr copy page= 2.5 page   so time taken in 30 page's copy =(10/2.5)= 
<gadget id="calculator">(10/2.5)</gadget>
<output>4</output>
4 hrs   ANSWER:4
<result>D</result>
subash can copy 50 pages in 10 hrs.subash and prakash together can copy 300 pages in 40 hours.in how much time prakash can copy 10 pages.