Rule: for a mixed number, keep the whole number and convert the fraction part to a decimal.

Mixed number	=	6 9/50
Keep the whole number 6. Convert 9/50 to a decimal: multiply numerator and denominator by 2. 9/50 = (9 x 2)/(50 x 2) = 18/100 = 0.18.
As decimal	=	6 + 0.18 = 6.18