Question

Ella is preparing for a 20-mile endurance cycling competition. She practices by cycling at a constant speed of 12 miles per hour for the first 4 miles. She increases her speed by 1.5 miles per hour every mile until she reaches 12 miles. After crossing 12 miles, she reduces her speed by 3 miles per hour each mile, till she reaches a speed of 15 miles per hour and keeps it constant until the end of her ride. From the graph shown below, find the interval where Ella's speed is increasing.

Answer 1

i think its 4 and 12 miles

Explanation:

Answer 2

[4, 12]

Explanation:

So even though we don't have the graph, we can still figure this out. We just have to read the passage carefully.

Notice how the question says: She increases her speed by 1.5 miles per hour every mile until she reaches 12 miles.

So from 4 miles to 12 miles we are increasing.

Our interval is [4, 12] :)