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?

Solution

Let the enlarged length of bacteria be x.

Actual length of bacteria = 5/50000 = 1/10000 cm = 10^-4 cm

Since the length of bacteria is directly proportional to the number of times the photograph is enlarged,

The actual length is 10^-4 cm

And, 5/50000 = x/20000

x = 2 cm

Answer

The enlarged length is 2 cm