9514 1404 393
Answer:
$125 per year
Step-by-step explanation:
In the 2 years from 2015 to 2017, the spending on lunches increased by ...
$800 -550 = $250
That is an average per year of ...
$250/(2 yr) = $125/yr . . . . average dollar increase per year
_____
<em>Additional comment</em>
For costs, it is often true that they follow an exponential curve, not a linear one. Ed's spending increased by a factor of 800/550 = 16/11 in the two years, so an average percentage increase of √(16/11) -1 = 20.6% per year.
3*5=15 15*8=120 Answer: 120m
Chris and Jim must replace a <em>total</em> quantity of 17 tyres.
<h3>What is the minimum number of tyres to be replaced?</h3>
In this problem we must use an inequality of the form f(x) ≥ a, where f(x) is the difference between the number of tyres replaced by Jim and the number of tyres replaced by Chris:
(25/20) · x - x ≥ 3
(5/20) · x ≥ 3
x ≥ 12
Then, the <em>minimum</em> number of tyres to be replaced is n = 15 + 12 = 17 tyres.
To learn more on inequalities: brainly.com/question/20383699
#SPJ1