$$\frac{3}{5} of \frac{5}{7} of \frac{2}{9} of 630 ?$$

Solution

We need to find the value of $$\frac{3}{5} \times \frac{5}{7} \times \frac{2}{9} \times 630$$

Note that $$630 = 2 \times 5 \times 7 \times 9$$
So, the value equals $$\frac{3}{5} \times \frac{5}{7} \times \frac{2}{9} \times 2 \times 5 \times 7 \times 9$$
Which equals $$3 \times 5 \times 2 \times 2 = 60$$