1. 957+3185 - x = 1634
4142 - x=1634
x= 1634+ 4142 => x =5.776
2. 837-253 - x = 194
584 - x = 194
x= 194+584 => x= 778
3. 235402 + a =236702
a = 236702 - 235402 => x = 1300
4. 53201 - a=23141
a=23141+53201 => a=76342
5. a+17123=25.432
a= 25.432-17.123 => a=8.309
6. a-25.754 = 14.123
a=14.123+25.754 => a =39.877