Question

8 technicians and 12 engineers can complete a work in 4 days, while 6 technicians and 14 engineers can complete it in 5 days. In how many days will 20 engineers complete it?

• A. 17.5 days
• B. 18 days
• C. 22.5 days
• D. 25 days
• E. 20 days

Answer 1

The correct option is E

20 days

Let 1 technician’s 1 day’s work = x

and 1 engineer’s 1 day’s work = y

Then, 8x+12y = $\frac{1}{4}$ and 6x+14y = $\frac{1}{5}$

Solving these two equations, we get: x = $\frac{11}{400}$, y = $\frac{1}{400}$

$\therefore$ 1 engineer’s 1 day’s work = $\frac{1}{400}$

$\Rightarrow$ 20 engineer’s 1 day’s work = $\frac{1}{20}$

So, 20 engineers will complete the work in 20 days.