Step-by-step explanation: He had to bake 240 cookies and on Monday he baked have of them which is 120 cookies. Then on Tuesday he baked a third of the remaining so if the baked 120 and has to bake 240 he still has to bake 120 now 1/3 * 120 = 40 so he baked 40 cookies on Tuesday on Wednesday he still has to bake the reaming cookies so 120 + 40 = 160 and 240 - 160 = 80 so on Wednesday he has to bake 80 cookies.
Well since I don't know what the original value I'll label it as X. So your equation will start out as X - (1.20 x 1) which would be for every hour for a half hour just divide 1.20 / 2 to get your half an hour. (1.20 x 3) + 0.60. Should be easy if they want it in faction form than it would just be 1.20 x 3 1/2.
