You need new tires. Bridgestone cost $33.95 per tire and Michelin cost $65.50. Michelin is more durable and will last longer. Both installation is $1.50 per tire. Bridgestone will last 20,000 miles. With MARR of 6% and you drive 10,000 miles per year, how many miles would Michelin have to last to make you indifferent in your choice?