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The traffic police recorded the speed (in km/hr) of 10 motorists as 47, 53, 49, 60, 39, 42, 55, 57, 52, 48. Later on an error in recording instrument was found. Find the correct average speed of the motorists if the instrument recorded 5 km/hr less in each case.

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Total Speed of `10` motorists `=47+53+49+60+39+42+55+57+52+48`
`=502` km/hr
Average Speed=Total Speed/10
`=502`/`10`
`=50.2` km/hr
Error in recording=`5` km/hr less
Actual Average Speed=`50.2 + 5`
`=55.2` km/hr
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