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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?

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Solution
Let the photograph of the bacteria be magnified 20,000 times, then the magnified length = x, ratio of the both
The given information, in the form of a table, is as follows:
Therefore, we obtain
Then 550000 = `x/(20,000)`
on multiplying thunderbolts
| Length of bacteria (in cm) | 5 | x |
| Bacteria enlarged | 50,000 | 20,000 |
50000 × x = 20000 × 5
`x = (20,000 × 5)/(50,000)`
x = 2
Hence, magnified length of bacteria = 2 cm
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