1. 10-0.76+3.4
=9.24+3.4
=12.64
2. 34.15-7.78-2.22-4.15
=(34.15-4.15)-(7.78+2.22)
=30-10
=20
3. 9.9+12.6
=10-0.1+12.6
=10+12.6-0.1
=22.6-0.1
=22.5
4. 15.63-1.37-1.63
=15.63-(1.37+1.63)
=15.63-3
=12.63
5. 5.32-1.56-3.44+1.68
=(5.32+1.68)-(1.56+3.44)
=7-5
=2