A and B can do a whole work in 5 days .if A increase his speed 2 times and B decrease his speed by half of the values the they can complete the task in 4 days.so,in how many A can complete the whole task?

• 1/a +1/b= 1/5 or 1/2a +1/2b= 1/10
  2/a+1/2b = 1/4
  1/a( 2-0.5) = 0.25-0.10=0.15
  1.5/a= 0.15
  a= 1/5/0.15=150/15= 10 days
• 12 years agoHelpfull: Yes(30) No(1)
• A+B=1/5;
  2A+B/2=1/4;
  ON SOLVING ABOVE EQUATIONS WE GET
  A=1/10;
  A CAN CMPLETE IN 10 DAYS
• 12 years agoHelpfull: Yes(15) No(1)
• correction,
  suppose a and b can work in x and y days respectively
  X+y=(1/5)and2x+(y/2)=(1/4) solving we get x=1/10 so a can finish work in 10 days
• 12 years agoHelpfull: Yes(2) No(0)
• answer is 10 days
  1/a+1/b=1/5
  1/2a+1/(b/2)=1/4
  solve above 2 eq u vl get A=10 days, b= 10 days
  
• 12 years agoHelpfull: Yes(2) No(1)
• let a and b can finish the work in x and y days respectively
  so,x+y=5and 2x+(y/2)=4 solving this two eq we can get x=1 so a can complete work in 1 days
• 12 years agoHelpfull: Yes(0) No(5)