Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

Mabel takes an express train to visit her grandparents each summer. Once the train reaches its cruising speed, it travels at a constant 8080 miles per hour for 240240 miles before it begins to slow down. The function D(t)D(t) represents the distance traveled by the train, in miles, after tt hours at cruising speed.\newlineWhat is the domain of D(t)D(t)?\newlineChoices:\newline(A)all real numbers from 00 to 8080\newline(B)all whole numbers from 00 to 33\newline(C)all real numbers from 00 to 33\newline(D)all whole numbers from 00 to 8080

Full solution

Q. Mabel takes an express train to visit her grandparents each summer. Once the train reaches its cruising speed, it travels at a constant 8080 miles per hour for 240240 miles before it begins to slow down. The function D(t)D(t) represents the distance traveled by the train, in miles, after tt hours at cruising speed.\newlineWhat is the domain of D(t)D(t)?\newlineChoices:\newline(A)all real numbers from 00 to 8080\newline(B)all whole numbers from 00 to 33\newline(C)all real numbers from 00 to 33\newline(D)all whole numbers from 00 to 8080
  1. Determine Domain of Function: We need to determine the domain of the function D(t)D(t), which represents the distance traveled by the train after tt hours at cruising speed.\newlineThe train travels at a constant speed of 8080 miles per hour.
  2. Calculate Time to Travel: To find the domain, we need to consider the time it takes for the train to travel 240240 miles at 8080 miles per hour.\newlineWe calculate the time by dividing the distance by the speed: t=240 miles80 miles per hourt = \frac{240 \text{ miles}}{80 \text{ miles per hour}}.
  3. Find Domain of D(t)D(t): Performing the calculation gives us t=3t = 3 hours.\newlineThis means that the train will take 33 hours to travel the 240240 miles at cruising speed.
  4. Find Domain of D(t): Performing the calculation gives us t=3t = 3 hours.\newlineThis means that the train will take 33 hours to travel the 240240 miles at cruising speed.The domain of D(t)D(t) is the set of all possible values of tt, which is the time in hours that the train travels at cruising speed.\newlineSince the train can travel for any fraction of time up to 33 hours, the domain includes all real numbers from 00 to 33.

More problems from Domain and range of linear functions: word problems