Please help me to simplify Linear expression

What signals you that factoring by grouping is the best method to use when factoring a problem?

Janet drove 300 miles in 4.5 hours. write an equation to find the rate at which she was traveling

You can ride your bike around your block 6 times and the whole neighborhood 5 times in 16 minutes. you can ride your bike around your block 3 times and the whole neighborhood 10 times in 23 minutes. how long does it take you to ride around the neighborhood?