Typist page speed

The typist typed 20 pages of text in 2 hours and 40 minutes. How many pages of text would she write at the same writing speed in 20 minutes?

Final Answer:

x =  2.5

Step-by-step explanation:

$$\begin{gathered} t_1=2:40=2hr40min=2+\frac{40}{60}=2.6667hr\doteq 2.6667 \\ {t}_2=0:20=0hr20min=0+\frac{20}{60}=0.3333hr\doteq 0.3333 \\ x=20\cdot \frac{t_2}{t_1}=20\cdot \frac{\frac{1}{3}}{\frac{8}{3}}=\frac{5}{2}=2\frac{1}{2}=2.5 \end{gathered}$$

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