An automotive store guaranteed its best tire for 50000 miles. A less expensive tire was guaranteed for only 20000 miles. The better tire had what percent greater performance than the less expensive one?

150%

Step-by-step explanation:

Best Tire : 50,000 miles

Better Tire : 20,000 miles

Difference : 50,000 - 20,000 = 30,000

The difference expressed as a percentage of the less expensive tire

= (30,000 / 20,000) x 100%

=150%