Răspuns:
1. 7001
6025
5757
2355
2. 5468
5889
5718
3. a+1513=3872=>a=3872-1513=>a=2359
a-2314=1573=>a=1573+2314=>a=3887
3727-a=1239=>-a=1239-3727=>-a=-2488=>a=2488
4. 35, 20, 45, 30, 40
5. 7x27=189
6. 3x(6+3)=3x9=27
5x(9-2)=5x7=35