Question

2upon 7×9upon 21×21upon 81×0upon1​

Answer 1

$\frac{2}{ \cancel7} \times \frac{9}{21} \times \frac{ \cancel{21}}{81} \times \frac{0}{1} \\ \\ 2 \times \frac{ \cancel9}{ \cancel{21}} \times \frac{ \cancel3}{ \cancel{81}} \times \frac{0}{1} \\ \\ 2 \times \frac{1}{7} \times \frac{1}{9} \times \frac{0}{1} = \frac{2}{63} \times 0 = \red0$