11 Days of Walking and Playing Badminton at My Friend's House

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AI Thread Summary
The discussion revolves around calculating the total number of days spent at a friend's house based on daily activities of walking and playing badminton. The participant initially guessed a total of 22 days but was corrected, as the activities did not account for the days of inactivity. After further analysis, it was concluded that there are three types of days: walking, badminton, and nothing, leading to a total of 16 days spent at the friend's place. The importance of creating a mathematical model to accurately solve the problem was emphasized. The final answer of 16 days was confirmed as correct, though it was noted that the initial approach involved guesswork.
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Homework Statement


I visited my friends home during my holidays.Our schedule went like this. We went for a walk in morning and played badminton in the evening. However due to the tiring nature of these, we did only 1 of them each day, i.e either walked or played Badminton. On some days we did neither!On 11 mornings we did nothing, 10 evenings we did nothing, we walked or played Badminton on a total of 11days. How long did i stay@ my friends place?


Homework Equations


How long did i stay @ my friends place?

The Attempt at a Solution


1 activity each day.
total activities=11 events=11 days (morning+evening)
11 mornings+10 eveings did nothing= 10 days + 1 morning.
so, i guess.. 11+11=22 days??

pls confirm the same.
 
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You should try to create a system of linear equations. Define a variable for each "activity", and do the sum.

If you do nothing in a morning, it doesn't say that you did nothing in the evening. Your answer is wrong.
 
If you do nothing in a morning, it doesn't say that you did nothing in the evening.

ok.
 
activity of 11 days = 11 Morn(M) and 11 evenings(E)
i.e. walk 6 M AND badminton 5 Evenings. This leaves 5 M AND 6 E.

OR

walk 5M and Badminton 6 E. this leaves 6M and 5E- no activity.considering first posssibilty leads nowhere.

But if we consider 2nd possibility;
now, 11 M and 10 E did nothing, including the activity days.
this leaves full day of no activity - 5 M and 5 E= 5 days

hence,
the total days= 11+5days=16 days.

pls confirm.
yahoo.
 
Last edited:
The answer is correct but the solution is guesswork. The goal of this exercise is to be able to create a mathematical model for the problem.

You have three kinds of day. 1- Walk, 2- Badminton, 3- Nothing. These are your three unknowns, there's also three equations in the question. It will be a lot easier that way than guessing and never be really sure of your answer. Try it!
 
thanks for guidance
 
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