Question

Calculează, grupând convenabil termenii.
10+20+ 30+ 40 =
22 +23+ 7 + 8 =
13 + 14 + 15 + 16 +17=
5 + 15 + 68 + 12 =
6 + 7 + 8 + 13 + 14 + 12 =
25 + 15 + 5 + 15 =
33 + 12 +28 + 7 =
22+25+18+15=
6+80+14=
1+2+3+27+28+29=
4+7+16+5+35=
18 + 19 + 15 + 1 +5+2=
12 + 16 + 18+ 14 =
25 +37 + 25 + 13 =
Mulțumesc ​

Answer 1

Explicație pas cu pas:

a)10+20+30+40=

r:(10+40)+(30+20)=50+50=100

b)22+23+7+8=

r:(22+8)+(23+7)=30+30=60

c)13+14+15+16+17=

r:(13+17)+(14+16)+15=30+30+15=60+15=75

d)5+15+68+12=

r:(5+15)+(68+12)=20+80=100

e)6+7+8+13+14+12=

r:(6+14)+(7+13)+(8+12)=20+20+20=40+20=60

f)25+15+5+15=

r:(25+5)+(15+15)=30+30=60

g)33+12+28+7=

r:(33+7)+(12+28)=40+40=80

h)22+25+18+15=

r:(22+18)+(25+15)=40+40=80

i)6+80+14=

r:(6+14)+80=20+80=100

j)1+2+3+27+28+29=

r:(1+29)+(2+28)+(3+27)=30+30+30=60+30=90

k)4+7+16+5+35=

r:(4+16)+(5+35)+7=20+40+7=60+7=67

l)18+19+15+1+5+2=

r:(18+2)+(19+1)+(15+5)=20+20+20=40+20=60

m)12+16+18+14=

r:(12+18)+(16+14)=30+30=60

n)25+37+25+13=

r:(25+25)+(37+13)=50+50=100