Fractions!

Question

Sam was planning his time during study week. He decided to allocate 5 days of 6 hours each to homework. He decided to spend 2/5 of the time on math, 10% of the total time on language arts, and 0.4 of the total time on his other subjects. If there was any time left he decided he would use it for social networking. How much time did Mike have for social networking, if any? (Answer the question using any method of your choice – either models, or numeric calculations showing your steps, etc).

Answer 1

Let x = time spent on social networking

 

Total study time = (5 days)(6hours/day) = 30 hours

 

(2/5)(30) + 0.10(30) + 0.4(30) + x = 30

 

12 + 3 + 12 + x = 30

 

                27 + x = 30      So, x = 3 hours