Question

7 of 30
Ashraf and Sham work together, they will complete a job in 10 days. If Ashraf works alone and completes half the job and then Sham takes over and completes the remaining
alone, they will be able to
complete the job in 20 days. How long will Sham alone take to do the job if Ashraf is as efficient as Sham?
cons :
O 10
O 20
O 30
40​

Answer 1

Answer:

sham on you idiot's mark me brilliant

Answer 2

Answer:

time taken by sham alone to complete the work = 20 days

Step-by-step explanation:

given, Ashraf and sham can together complete the job in 10 days

if the do half part of the work, it takes 20 days to complete the whole work

$\frac{1}{t1} +\frac{1}{t2} = \frac{1}{t}$

assume, Ashraf takes x days to complete half of the work

ashraf's one day work = $\frac{1}{2x}$

sham's one day work = $\frac{1}{2(20-x)}$

$\frac{1}{2x} + \frac{1}{2(20-x)} = \frac{1}{10}$

$\frac{1}{x} + \frac{1}{20-x} = \frac{2}{10}$

$\frac{20-x+x}{20x-x^{2} } = \frac{1}{5}$

⇒x²-20x+ 100 = 0

x+y = 20 and xy = 100

values of x= 10, 10

given, ashraf is as efficient as sham

time taken by ashraf to complete the work alone = $\frac{1}{2*10}$ = $\frac{1}{20}$

              = 20 days

time taken by sham to complete the work alone = $\frac{1}{2(20-10)}$ =$\frac{1}{20}$

             = 20 days