?% of 280 + 18% of 550 = 143.8 (a) 11 (b) 18 (c) 21 (d) 16 (e) None of these
(?/100)*280+(18/100)550=143.8(?*28 + 18*55)/10 =1438/10?*28 +18*55 =1438?*28 + 990=1438?*28 = 1438-990?*28 = 448? = 448/28? = 16