Two machines, working simultaneously at their respective constant rates, can print 400 sheets in 5 hours. If one machine can print 200 sheets in 3 hours, what is the rate of the other machine, in sheets per hour?
选项
A.
B.
C.
D.
80
E.
200
解析
设两台机器分别为A和B
5小时内:A + B = 400张
1小时内:A + B = 80张
设机器A在3小时内打印200张纸
因此,机器A每小时可打印\(\frac{200}{3}\)张纸
因此:
\[
\begin{align*}
\frac{200}{3} + B &= 80 \\
B &= \frac{40}{3}
\end{align*}
\]
因此,答案为选项A。