John saves 5 fifty-cent coins in the first week. He saves 6 fifty-cent coins in the
second week. In the third week, he saves 7 fifty-cent coins and so on. How many
fifty-cent coins can John save altogether by the end of 10 weeks?
+321 If I understand the question correctly our equation is (5*0.5) + (6*0.5) + (7*0.5) + (8*0.5) + (9*0.5) + (10*0.5) + (11*0.5) + (12*0.5) + (13*0.5) + (14*0.5) = $47.5.
He saves 95 fifty-cent coins in 10 days
+37146 an = 5 + (n-1) Arithnetic Sequence
sum10 = n/2 ( a1+a10)= 10/2 ( 5 + 14) = 190/2 = 95 coins saved in 10 weeks
