67+9+1+9+1+9+3+1+4+7+7+7+7+8+9+3+6+2
=67+9+9+9+9+1+1+1+3+3+7+7+7+7+8+6+2
= 67+9.4+1.3+3.2+7.4+8+6+2
= 67 + 36 + 3 + 6 +28 + 8 + 6 + 2
= (67+3)+(28+2)+36+6+6+8
= 70 + 30 +36+6+6+8
= 100 +36+ 20
= 100 + 56
= 156
160 nha
dễ quá bằng 150 nha
Đáp số : 160