Question

Afla numarul necunoscut: a+989=2007;2196+b=4015;c-1917=3595;10000-d=3480;a+(980+796)=4000; (2901+6156)-b=5435;c-(10000-8903)=3679;(9980-7675)-d=980.

Answer 1

a+989=2007
a=2007-989
x=1018

2196+b=4015
b=4015-2196
b=1819

c-1917=3595
c=3595+1917
c=5512

10000-d=3480
d=1000-3480
d=6520

a+(980+796)=4000
a+1776=4000
a=4000-1776
a=2224

(2901+6156)-b=5435
9057-b=5435
b=9057-5435
b=3622

c-(10000-8903)=3679
c-1097=3679
c=4776

(9980-7675)-d=980
2305-d=980
d=2305-980
d=1325

Answer 2

a=2007-989
a=1018
b=4015-2196
b=1819
c=3595+1917
c=5512
d=10000-3480
d=6520
a=4000-1776
a=2224
b=9057-5435
b=3622
c=1097+3679
c=4776
d=2305-980
d=1325