Amy runs 6 miles in 45 minutes. at the same rate, how many minutes would she take to run 4 miles?

Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?

What is the measure of angle x? a.101 b.158 c.44 d.79