Least count of measuring instrument is the least value of physical quantity that can be measured accurately using the instrument.

For ex...
             Take a simple scale (Length measuring instrument) of 15 cm. In this scale, you can see that 1 cm is divided into 10 equal parts. Therefore, the least value can be measured is 1cm/10=0.1cm or 1 mm which is least count of this instrument.
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The Brainliest Answer!
1)see the main division let us take in ammeter it is 0 to 1 that is 1
2)then see the number of divisions between 0 to 1 let it be 10
3)divide 1/10 = 0.1
4)now the least count is 0.1
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