The next progression after 5=20 is 4=12, but they skipped this number and asked for 3=?. Had they shown 4=12 then 3=6 would be the answer. However, I have no idea how you have a progression that goes 9, 8, 7, 6, 5, 3 with a corresponding progression of 72, 56, 42, 30, 20, ?. If you show the 4 in the progression with the corresponding 12 then everything is fine, but if you don't then some other pattern may be at play. Once possible pattern is--
x = x - (10 \ x) this gives the progression 9, 8, 7, 6, 5, 3
the other side of the equal sign uses a corresponding progression of--
x = (x - (10 \ x )) * (x - (10 \ x ) - (10 \ x)) this gives the progression 72, 56, 42, 30, 20, 3
So, the answer is 3
x = x - (10 \ x) this gives the progression 9, 8, 7, 6, 5, 3
the other side of the equal sign uses a corresponding progression of--
x = (x - (10 \ x )) * (x - (10 \ x ) - (10 \ x)) this gives the progression 72, 56, 42, 30, 20, 3
So, the answer is 3
BA Liberal Studies from Thomas Edison State University
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