👤

ajutorrr toate exercitii

Ajutorrr Toate Exercitii class=

Răspuns :

1.)9+12=21.
7/10+2/10=9/10.
210/10+9/10=219/10m.
2.)6/13+2/13=8/13.
3.)7/29-5/29=2/29.
4.)a)1/17+2/17+3/17+...+39/17=
(1+2+3+...+39)/17=
=(39×40:2)/17=
=(39×20)/27=
=780/27=
=260/9.
b)