Question

Aflativ nr necunoscut din următoarele expresii matematice: (525:5+b):5+12=790;(65×502:10-c-63):3=600;[(e:8+5 609):2-111]:10=400;(540:6×9-755):(g-386)=5

Answer 1

a) (525:5+b):5+12=790
(105+b):5=790-12
21+$\frac{b}{5}$=778
$\frac{b}{5}$=778-21
$\frac{b}{5}$=757
b=757·5
b=3785

b) (65×502:10-c-63):3=600
32630:10-c-63=600×3
3263-c-63=1800
3200-c=1800
c=3200-1800
c=1400

c)  [(e:8+5609):2-111]:10=400
(e:8+5609):2-111=400×10
(e:8+5609):2=4000+111
e:8+5609=2×4111
e:8=8222-5609
e:8=2613
e=8×2613
e=20 904

d) (540:6×9-755):(g-386)=5
(90×9-755):(g-386)=5
(810-755):(g-386)=5
55:(g-386)=5
g-386=55:5
g=11+386
g=397