Neco 2022 Commerce Question 9

An advertiser plans a 4‑week TV campaign. Each day the ad will be aired \(a\) times on Channel A (rating \(4.5\) points per airing, cost \(\text{₦}150{,}000\) per airing) and \(b\) times on Channel B (rating \(3.2\) points per airing, cost \(\text{₦}120{,}000\) per airing). The target market size is 2,000,000 people. The campaign must achieve at least 250 GRPs and the total cost must not exceed \(\text{₦}30{,}000{,}000\). Determine the minimum integer values of \(a\) and \(b\) (both at least 1) that satisfy both constraints while minimizing the total daily airings \(a+b\). Also give the total GRPs and total cost for the whole 4‑week period using those values.