<span>The pair of integers that I chose are:
(a) sum is –3
5 + (-8) = -3
(b) difference is –5
2 - 7 = -5
(c) difference is 2
14 -12 = 2
(d) sum is 0
2 - 2 = 0</span>
The school can buy fifteen notebooks and nineteen tablets. 15X7=105 and 5X19=95. 95+105=200. The first thing you want to do is realize that 5Xanything will give you an answer that has a 0 or a five at the end, so you want to find a product by 7 that ends with a 0 or 5 too.
600 ---> 250
600 - 250 = 350
350 / 5 = 70
Average decrease in value per year: $70