Using the place value chart we can see that the decimal 0.6 is six tenths, so we can write 0.6 as the fraction 
. Notice however that is not in lowest terms so we need to divide the numerator and the denominator by the greatest common factor of 6 and 10 which is 2.
-Image Provided-
Diameter= approx. 50.27
Circumference= approx. 25.13
He would use 2 musical notes because 4/2 is 2.
