Answer:
If the scatter plot was made with weekly data (x axis in "weeks")
y= 17.63(5)+27.52 = 115.67 (money saved)
If the scatter plot was made with daily data (x axis in "days")
y= 17.63(5*7)+27.52 = 644.57 (money saved)
Explanation:
We just need to apply the equation found by Adan with his model and substitute depending on wether his plot was on days or weeks.