Terry and Jerry had 320 stamps and 180 stamps respectively when rounded to the nearest ten.
(a) What is the minimum possible number of stamps they have altogether?
(b) What is the maximum possible number of stamps they have altogether?
(c) What is the maximum possible difference in the number of stamps betweenTerry and Jerry?
(d) What is the maximum possible difference in the number of stamps betweenTerry and Jerry?
