Calculate what is in brackets and approximate it. After calculation in brackets, it is 120. At this point, the formula becomes

40* 120* 120 120* 120 6* 120 40

—————— = —————— = —————— =——————

20*20*22* 18 10*22* 18 1 1* 18 1 1

Finally it becomes 40/ 1 1.

Hope to adopt