Zack bought a cost for 69.78. he paid with $100 bill and received 26.73 in change. how much was the sales tax.

hello from mrbilldoesmath!

answer:

a(n) - a(n-1) -3

discussion:

this ones a bit interesting. given a(n) = 5 - 3n consider this:

a(n-1) = 5 - 3(n-1)

          = (5 - 3n) + 3             => but a(n) = 5 - 3n, the first term

          = a(n)   + 3                 => subtract 3 from both sides

a(n-1) -3 = a(n)  

or

a(n) - a(n-1) -3

you,

mrb

answer: jasmine will bake 4/3 or 1 1/3 cookies in an hour

step-by-step explanation:

if u add 1/3 every 15 minutes after an hour u will have 4/3 or 1 1/3