Question

va rog tot dar fara ex 10 si 11

Answer 1

5. a citit 1/3 din carte, inseamna ca a ramas 2/3 din carte=60 pagini
2/3·c=60 |:2
1/3 c=30
c=3·30
c=90, raspuns C
6. a/b=3/4
b-a=7
b=?
a/b=3/4
a=3k, b=4k, k∈N
4k-3k=7
k=7
b=4·7=28
raspuns B
7. 2h si 15 min=2·60+15=120+15=135 min
raspuns D
8. 2·12,2+4,6=24,4+4,6=29
raspuns B
9. patratul nr 1,2=1,2²=1,44 nu are corespondent
cubul nr 0,2=0,2³=(2/10)³=2³/1000=0,008 nu are corespondent
produsul nr 0,144 si 10²=0,144·100=14,4 ⇒4)
catul nr 0,2 si 0,25=0,2:0,25=1/5:25/100=1/5:1/4=1/5·4/1=4/5=0,8⇒3)