A glazed doughnut contains 200 calories. Suppose you eat one doughnut, and then decide to exercise to burn off the calories. Use the given table to list all possible sets of exercises that will burn off the calories in 1 hour. Exercise Calories/hr Walking 150 Biking 420 Jogging 500 Enter your answers in set notation using w for walking , b for biking , and j for jogging . If there is more than one correct answer, separate them with commas. If there is no such set, enter $\varnothing $ .
A) {j}, {j, b}, {j, w}, {j, b, w}, {b}, {b, w}
B) {j}, {b}, {w}
C) {j}, {j, b}, {j, w}, {j, b, w}, {b}, {b, w}, {w}
D) {j}, {j, b}, {j, w}, {j, b, w}
E) $\varnothing $

Question

Quizplus · Accepted Answer

The total calories burned for each set must be 200 or greater, and the sets in choice A (j, j+b, j+w, j+b+w, b, b+w) all meet this requirement. The sets in choices B, C, and D do as well, but they include some less efficient forms of exercise (walking and/or jogging) that are not necessary to achieve the goal. Choice E is incorrect because there are at least 2 sets that work.

A Glazed Doughnut Contains 200 Calories ∅\varnothing ∅ A) {J}, {J, B}, {J, W}, {J, B, W}

A Glazed Doughnut Contains 200 Calories $\varnothing$
A) {J}, {J, B}, {J, W}, {J, B, W}