Mark ran a mile in 7 1/2 minutes. His brother ran a mile in 6 1/6 minutes. How much more time does Mark take to run the mile?

When y’all answer can y’all explain too !

Girardo is using the model below to solve the equation . girardo uses the following steps: step 1 add 4 negative x-tiles to both sides step 2 add 1 negative unit tile to both sides step 3 the solution is which step could be adjusted so that gerardo's final step results in a positive x-value? in step 1, he should have added 4 positive x-tiles to both sides. in step 1, he should have added 3 negative x-tiles to both sides. in step 2, he should have added 4 negative unit tiles to both sides. in step 2, he should have added 1 positive unit tile to both sides.

Which of the following is an example of a rational number? a. π b. √ 9 c. √ 8 d. 3.8362319