Question

am un ex 12 efectueaza utilizand factorul comun
a) 110+220+330+440+550
b) 5+10+15+20+25+30+35
c) 123*389+123*11-100*123
d) 739*2016-2016+262*2016
f) 11001+22002+33003+44004+55005
g) 6+12+18+24+30+36+42
h) 719*2017-2017*1999-2*1998
i) 1999*2000-1998*1999-2*1998
mulțumesc

Answer 1

Răspuns:

a) 110+220+330+440+550 =

=110x(1+2+3+4+5)=

=110x15=

=1650

b) 5+10+15+20+25+30+35 =

=5x(1+2+3+4+5+6+7)=

=5x28=

=140

c) 123*389+123*11-100*123 =

=123x(389+11-100)=

=123x300=

=36900

d) 739*2016-2016+262*2016 =

=2016x(739-1+262)=

=2016x1000=

=2016000

f) 11001+22002+33003+44004+55005 =

=11001x(1+2+3+4+5)=

=11001x15=

=165015

g) 6+12+18+24+30+36+42 =

=6x(1+2+3+4+5+6+7)=

=6x28=

=168

h) 719*2017-2017*1999-2*1998=

=2017x(719-1999)-3996=

=2017x(-1280)-3996=

=-2581760-3996=

=-2585756

i) 1999*2000-1998*1999-2*1998=

=1999x(2000-1998)-3996=

=1999x2-3996=

=3998-3996=

=2

Explicație pas cu pas: