problem-1.10

problem-1.10  The sales figures are entered in with
> H2 = c(2700,2600, 3050, 2900, 3000, 2500, 2600, 3000, 2800,
+ 3200, 2800, 3400)
> cumsum(H2)
 [1]  2700  5300  8350 11250 14250 16750 19350 22350 25150 28350
[11] 31150 34550
> diff(H2)
 [1] -100  450 -150  100 -500  100  400 -200  400 -400  600
    
We see that there were 34,550 sold, December had the greatest increase (600), and June had the largest decrease (-500).