Book: NCERT - Mathematics
Chapter: 13. Direct and Inverse Proportions
Subject: Maths - Class 8th
Q. No. 5 of Exercises 13.1
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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?
Let the actual length of the bacteria be x cm and enlarged length be y cm when it is enlarged 20,000 times.
The given information in the form of table is as follows
Length of bacteria in cm | 5 | x | y |
Number of times the photograph of bacteria was enlarged | 50,000 | 1 | 20,000 |
The above information is in direct proportion.
Therefore,
5/50,000 = x/1
→x = 10-4 cm
Hence the actual length of bacteria is 10-4 cm
5/50,000 = y/20,000
→y = 2 cm
Hence, the enlarged length of bacteria when it is enlarged 20,000 times is 2cm
Chapter Exercises
More Exercise Questions
A mixture of paint is prepared by mixing 1 part of red pigments with 8 parts of base. In the following table, find the parts of base that need to be added.
Parts of Red Pigment | 1 | 4 | 7 | 12 | 20 |
Parts of base | 8 |