Question

(11+12+13+....+100):37 Suma lui gaus

Answer 1

(11+12+13+....+100):37 =

= [(1+2+3+...+100) - (1+2+3+...+10)] : 37 =

= [100 × (100+1) : 2 - 10 ×(10+1) : 2] : 37 =

= (50 × 101 - 5 × 11) : 37 =

= (5050 - 55) : 37 =

= 4 995 : 37 =

= 135

Answer 2

(11+12+13+....+100):37=
=[(1+2+...+100)-(1+2+..+10)]:37
=(100·101:2-10·11:2):37
=(5050-55):37
=4995:37
=135