Question

A photograph of a bacteria enlarged 50,000 times attains a length of 5 cm as shown in the diagram. What is the actual length of the bacteria? If the photograph is enlarged 20,000 times only, what would be its enlarged length in cm?

• A. ${10}^2,8$
• B. ${10}^{-4},2$
• C. ${10}^{-3},6$
• D. ${10}^{-4},4$

Answer 1

Answer: (B)

Let the actual lenght of the bacteria be $x$ cm

When the photograph of bacteria is enlarged $50,000$ times .

i.e $x$ x $50,000=5$ cm

$\therefore x={10}^{-4}$ cm

Now. when the photo of bacteria is enlarged $20,000$ times,

length of bacteria will be

${10}^{-4}$ x $20,000=2$ cm

Answer is ${10}^{-4},2$ cm