Chapter 7 - Measurement - 7.3 The Metric System - Capacity and Weight (Mass) - 7.3 Exercises - Page 503: 48

0.9 g

900 mg to g Unit for the answer (g) is in numerator; unit being changed (mg) is in denominator so it will divide out. The unit fraction is $\frac{1 g}{1000 mg}$. Multiply 900 mg times to the unit fraction 900 mg * $\frac{1 g}{1000 mg}$ = 0.9 g