5 • (40 + 6) = 5 • 40 + 5 • 6 = 230
6 • (50 + 4) = 6 • 50 + 6 • 4 = 324
7 • (20 + 8) = 7 • 20 + 7 • 8 = 196
5×(40+6)=5×40+5×6=230
5×46 =230
6×(50+4)=6×50+6×4=324
6×54=324
7×(20+8)=7×20+7×8=196
7×28=196