There a Error in your Question At first it say "Mary" and then "Toby" at the end.
Answer:
$68.90
Explanation:
If She bought them separately:
Jean: $30 x 6%=$1.80
30+1.80=31.80
Sweater: $35 x 6%=$2.10
$35+$2.10=$37.10
$31.80+$37.10= $68.90
Hence, Toby Spend $68.90 on Jeans and Sweater.