my $sales = {
monday => { jim => [ 2 ], mary => [ 1, 3, 7 ] },
tuesday => { jim => [ 3, 8 ], mary => [ 5, 5 ] },
wednesday => { jim => [ 7, 0 ], mary => [ 3 ] },
thursday => { jim => [ 4 ], mary => [ 5, 7, 2, 5, 2 ] },
friday => { jim => [ 1, 1, 5 ], mary => [ 2 ] },
};

my $commissions = $sales->{tuesday}{jim};
my $num_sales   = @$commissions;
my $total       = 0;
foreach (@$commissions) {
    $total += $_;
}
print "Jim made $num_sales sales on Tuesday and earned \$$total commission\n";