Unless you just want to give money to the ice cream truck, for 0 items, you will pay 0.
Since the price of each item is $0.77, for one item you will pay $0.77. (Is that a surprise?)
Then for two items, you will pay $0.77 for each one, or $0.77 + 0.77 = $1.54. You can also compute this by making use of the fact that multiplication is a shortcut for repeated addition. The price can be found by $0.77×2 = $1.54 = f(2).
Similarly, for 3 items, you can add $0.77 three times: $0.77 + 0.77 + 0.77 = f(3), or you can use multiplication: $0.77×3 = $2.31 = f(3).
a) Our table looks like
(x, f(x))
(0, 0)
(1, 0.77)
(2, 1.54)
(3, 2.31)
b) By now, I'm sure you have realized that to find the price of x items, you multiply 0.77 by x.
f(x) = 0.77x
............................
Multiply the amount of the notebooks which is 3, by the cost of the notebook, which is $15.85. that is $47.55.
to find how much it costs with the coupon, do the notebook cost and subtract that by 0.75
$47.55 - 0.75 = $46.8
J ---- P --- K
JP = 2x
PK = 7x
JK = 27
2x + 7x = 27
9x = 27
x = 27/9
x = 3
The value of P is 3.
JP = 2x = 2(3) = 6
PK = 7x = 7(3) = 21