Question

Writing and evaluating a function that models a real-world situation: advanced

ravi is putting money into a savings account. he starts with $350 in the savings account, and each week he adds $70.

let S represent the total amount of money in the savings account (in dollars), and let W represent the number of weeks ravi has been adding money. write an equation relating S to W. then use this equation to find the total amount of money in the savings account after 17 weeks.

equation: ?
total amount of money after 17 weeks: $?

Answer 1

So in this equation we're given that Ravi puts $350 into his account, this means that when W=0, S=350. Or that the y-intcpt(b) is 350.

when we find an equation we use slope intcpt formula:

y = mx + b

M in this case is the slope or the amount S

changes for every value of W. So if Ravi adds $70 every day that means the amount of money in his account increases by $70 everyday, so we can say m= 70

So putting together the equation with b= 350 and m = 70 we get :


`S = 70W + 350 \:`

Calculating for 17 weeks or W = 17


`S = \: 70 * 17 \: + 350 \\ S = 1190 \: + 350 = 1540`

Ans: $1540