Percent Change = (new quantity - old quantity) / old quantity
#2:
(64 - 52) / 52
12 / 52
0.2308
23%
#4:
(12 - 18) / 18
-6 / 18
-0.33
33% decrease
#5:
(10 - 16) / 16
-6 / 16
-0.375
38% decrease
Hope this helps! :)
