Question

1,2,5,6

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Answer 1

1)
x=[(30+1)x10-23]:7
x=(31x10-23):7
x=(310-23):7
x=287:7
x=41

y=[(5x5-20)x2-6
y=(25-20)x2-6
y=5x2-6
y=10-6
y=4

x>y, raspuns corect b)

2) (30·x+6):4=84
30·x+6=84·4
30·x+6=336
30·x=336-6
30·x=300
x=300:30
x=10

5) b=biciclete
t=triciclete

b+t=15
2xb+3xt=38   (2=roti biciclete; 3=roti triciclete)

b+t=15
2b+3t=38
t=15-b
2b+3(15-b)=38
2b+45-3b=38
3b-2b=45-38
b=7

Raspuns: 7 biciclete

6)
a-b=936
b=a:4

a-a:4=936   (inmultim cu 4)
4a-a=3744
3a=3744
a=3744:3
a=1248
b=1248:4
b=312

Deci nr.sunt:
a=1248
b=312