A wire of length 6 m is stretched such that its radius is reduced by 20%. Which one of the following is the value of increase in its length ?

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Submitted by examrobotsa on

Q: 118 (CAPF/2020)
A wire of length 6 m is stretched such that its radius is reduced by 20%.
Which one of the following is the value of increase in its length ?

question_subject: 

Maths

question_exam: 

CAPF

stats: 

0,6,4,0,6,3,1

keywords: 

{'radius': [0, 0, 2, 2], 'increase': [3, 1, 10, 35], 'length': [0, 0, 1, 0], 'wire': [0, 0, 7, 16], 'value': [0, 0, 1, 0]}

Option 1: 50%

This option suggests that the increase in length is 50%. However, this is incorrect. The increase in length cannot be 50% because the wire is being stretched and its radius is reduced by 20%.

Option 2: 56-25%

This option suggests that the increase in length is 56-25%. This can be simplified to 31%. This means that the length of the wire increases by 31%.

Option 3: 62-25%

This option suggests that the increase in length is 62-25%. This can be simplified to 37%. This means that the length of the wire increases by 37%.

Option 4: 75%

This option suggests that the increase in length is 75%. However, this is incorrect. The increase in length cannot be 75% because the wire is being stretched and its radius is reduced by 20%.

The correct answer is option 2, which states that the value of increase in length is 31%. This means that the length of the wire increases by 31%.