Given :
Nathan smiled at 50 people one day and recorded that 36 people smiled back at him.
To Find :
How many people should Nathan expect to return a smile if he smiles at 650 people over a period of time.
Solution :
Ratio of people smiled by total number of people is :
![R = \dfrac{36}{50}](https://tex.z-dn.net/?f=R%20%3D%20%5Cdfrac%7B36%7D%7B50%7D)
Now, it is given that we have to use the given conditions.
Therefore, ratio will be same :
![\dfrac{s}{650}=\dfrac{36}{50}\\\\s = \dfrac{36}{50}\times 650\\\\s = 468](https://tex.z-dn.net/?f=%5Cdfrac%7Bs%7D%7B650%7D%3D%5Cdfrac%7B36%7D%7B50%7D%5C%5C%5C%5Cs%20%3D%20%5Cdfrac%7B36%7D%7B50%7D%5Ctimes%20650%5C%5C%5C%5Cs%20%3D%20468)
Therefore, number of smiles Nathan expect to return is 468.
y= -1x -3
that's equation of the line
Y=68+4x
100=68+4x
-68=-68
32=4x
Divide both sides by 4
x=it will take 8 min. for the water to reach 100 degrees
y=total degrees
x=# of minutes