👤
Popescumihaela11
a fost răspuns

1)2+4+6+...+2018
2)5+10+15+...2020

Răspuns :

Desteptu119
1. (2018+2)×((2018-2)÷2+1)÷2=
=2020×(2016÷2+1)÷2=
=2020×1009÷2=
=2038180÷2=
=1019090

2. (2020+5)×((2020-5)÷5+1)÷2
=2025×(2015÷5+1)÷2=
=2025×404÷2=
=818100÷2=
=409050

Alte intrebari