Combine JSON files and recalculate percentages with JQ

In terms of your intermediate results "A" and "B" (denoted below by $a and $b), the following filter produces the required answer. The key is transpose:

($a | [.hits_percents, .visitors_percents, .bytes_percents] | transpose)| . as $v| reduce range(0; length) as $i    ($b;       .[$i].hits.percent = $v[$i][0]      | .[$i].visitors.percent = $v[$i][1]     | .[$i].bytes.percent = $v[$i][2] )

There is probably a better way to get the final result, but you asked how the two intermediate results can be combined....

Bonus question:

 # Round a (positive) percentage to two decimal places: def percent:   ((1000 * .) | floor)   | (. % 10) as $r   | ((. / 10) | floor) as $answer   | if $r > 4 then ($answer + 1) else $answer end   | . / 100   ;

This could be used by adding map(map(percent)) after the transposition:

def percent:  ((1000 * .) | floor)  | (. % 10) as $r  | ((. / 10) | floor) as $answer  | if $r > 4 then ($answer + 1) else $answer end  | . / 100;($a | [.hits_percents, .visitors_percents, .bytes_percents] | transpose)  | map(map(percent))  | . as $v  | reduce range(0; length) as $i      ($b;         .[$i].hits.percent = $v[$i][0]        | .[$i].visitors.percent = $v[$i][1]       | .[$i].bytes.percent = $v[$i][2] )