Question

(525:5+b):5+12=790 (65X502:10-C-63):3=600

Answer 1

(525:5+b):5+12=790
105+b:5+12=790
105+b:5=790-12
105+b:5=778
105+b=778 ori 5
105+b=3890
b=3890-105
b=3785

(65 ori 502:10-C-63):3=600
(32630:10-C-63):3=600
(3263-C-63):3=600
3263-C-63=600 ori 3
3263-C-63=1800
C-63=1800+3263
C-63=5063
C=5063+63
C=5126

Answer 2

1)  (525:5+b):5+12=790
(105+b):5+12=790/-12
(105+b):5=778/*5
105+b=3890/-105
b=3785
Verificare:
(105+3785):5+12=790
3890:5+12=790
778+12=790
790=790 (A)

2) (65x502:10-c-63):3=600
(32630:10-c-63):3=600
(3263-c-63):3=600/*3
3263-c-63=1800/+63
3263-c=1863
c=3263-1863
c=1400
Verificare:
(65x502:10-1400-63):3=600
(32630:10-1400-63):3=600
(3263-1400-63):3=600
(1863-63):3=600
1800:3=600
600=600 (A)