ա) 531+1053:117-(443-399:57=
1053:117=9
9+531=540
399:57=7
443-7=436
540-436=104

բ) 57.2452+818-(338-78:78)
78:78=1
338-1=337
2452×57=139764
139764+818=140582

537.

13×2=26

8×3=24

26+24=50

58-50=8

535. 893=800+90+3

27=20+7

9=9

25679=20000+5000+600+70+9