Answer :

DarkBlue
10.39-4.28=6.11
Have a nice day!! ^^
Billymkhoi
10.39≈ 10.30
4.28≈ 4.30

10.39- 4.28
≈ 10.30- 4.30
≈ 6

The estimate for 10.39- 4.28 is 6~