A and B, working together, can complete a work in 16 days, C and A together can complete it in 32 days, B and C together can completeit in 24 days. They worked togetherfor 12 days. In how many days will C alone complete the remaining work ?
Let A, B and C can finish the work in x, y and z days respectively.
So, A's one day's work $$=\dfrac{1}{x}$$
B's one day's work $$=\dfrac{1}{y}$$
C's one day's work $$=\dfrac{1}{z}$$
A and B working together can complete the work $$=16$$ days.
So, A and B together will finish the work in one day, $$\dfrac{1}{x}+\dfrac{1}{y}=\dfrac{1}{16}$$ ------(i)
C and A together can finish the work in $$=32$$ days
So, C and A together will finish the work in one day $$\dfrac{1}{x}+\dfrac{1}{z}=\dfrac{1}{32}$$ ------(ii)
B and C together can finish the work in $$=24$$ days
So, B and C together can finish the work in one day $$\dfrac{1}{y}+\dfrac{1}{z}=\dfrac{1}{24}$$-----(iii)
Now, From equation (i), (ii) and (iii)
$$\dfrac{1}{x}+\dfrac{1}{y}+\dfrac{1}{x}+\dfrac{1}{z}+\dfrac{1}{y}+\dfrac{1}{z}=\dfrac{1}{16}+\dfrac{1}{32}+\dfrac{1}{24}$$
$$\dfrac{2}{x}+\dfrac{2}{y}+\dfrac{2}{z}=\dfrac{13}{96}$$
$$\dfrac{1}{x}+\dfrac{1}{y}+\dfrac{1}{z}=\dfrac{13}{192}$$
Hence, if they are working together, they can finish the work in one day $$=\dfrac{13}{192}$$
Substituting the value from the equation (i)
$$\dfrac{1}{z}=\dfrac{13}{192}-(\dfrac{1}{16})$$
$$\dfrac{1}{z}=\dfrac{13-12}{192}$$
$$\dfrac{1}{z}=\dfrac{1}{192}$$
So, C can finish one work in $$192$$ days.
As per the question, they worked for$$12$$days,
So, remaining work after $$12$$days $$=1-\dfrac{12\times13}{192}$$
 $$=\dfrac{192-156}{192}$$
 $$=\dfrac{36}{192}$$
 C can finish one work in 192 days
Hence, C can finish $$\dfrac{36}{192}$$ work in $$=\dfrac{192\times36}{192} =36$$days
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