Answer:
s = 45w
Explanation:
Jeremiah is saving money for a tutoring job. 
He saved $135 after 3 weeks. 
Therefore, his saving per week = 

= 

= $45
If he works for w weeks then at the same rate total amount saved by him will be 
= $45w
If this amount is equal to $s then equation that represents the total saving after w weeks will be 
s = 45w