Answer:
40th and 80th visit
the first visit where you receive both is the 40th
Step-by-step explanation:
personally, I believe that the simplest way to solve this is use an excel spreadsheet to see which visits would include both a free beverage and a free appetizer:
- both rewards would happen only twice, at the 40th and 80th visit.
you can also calculate it mathematically since multiples of 8 and 10 do not repeat themselves very much, only when 8 is multiplied by 5 and 10.
We can assume that the shape is a rectangular prism by the given dimensions
Volume of a rectangular prism
Volume = Area of Base × Height of prism
= Length × Width × Height of prism
Substitute!
168 = L × 7 × 3
168 = L × 21
Divide 21 on either sides to isolate L

=

21 and 21 cancels out
8 = L
L = 8 yd
= 12 + (- 6)(n - 1 )
This is an arithmetic sequence with n th term
=
+ (n - 1)d
here d = - 6 - 0 = 0 - 6 = 6 - 12 = -6 and
= 12, hence
= 12 + (- 6)(n - 1)
use this formula to find the 30 th term
= 12 + (- 6 × 29) = 12 - 174 = - 162
<span>-37 n = -56
n=</span>-56/<span>-37
n=56/37 or ~1.51</span>