Afla nr. necunoscut:b)8xa:2-1009=191
c)20x35:7+ax2-40:2=180
d)30x6:a+92x5-36x11=84
e)6488xa;5:4=4866
f)10x24:40xa:20=15
g)3600+86-540+a-90+48=3201
h)547-218+a-154+78=279