## Elementary Algebra

When we multiply fractions, we multiply the numerators of the fractions by each other and the denominators of the fractions by each other. Thus, we obtain that this expression is equal to: $\frac{5 \times 3}{9 \times 10}=15/90$ In order to simplify fractions, we want to cancel out anything that is in both the numerator and the denominator of the fraction. In order to do this, we look for common factors for the values in the numerator and the denominator of the fraction. 90 and 15 have a common factor of 15, so we simplify: $15/90=15/(15*6)=1/6$