91+9○9+9168+7○48+7100-45○6555-40○15

Question

91+9○9+91
68+7○48+7
100-45○65
55-40○15

Answer 1

91+8=100
100•100=10000
68+7=75
75•55=573
100-45•65=3575
55-40•15=225..........