Efectuați:
1. ( 90 – 30 ) : 2 +242 + 244 x ( 40 x 20 : 10 + 6 ) =
2. 10 x 10 : 10 :10+10 – 10 =
3. ( 50 x 2 ) + ( 90 x 3 ) – ( 64 : 2 ) + ( 68 x 5 ) =