On or elimination to solve. 12) Five hats and three scarves cost $99.
While three hats and five scarves cost $85.
Find the cost of one hat and one scarf.

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is