Question

Calculeaza 200+199-198+197+196-195+....+5+4-3+2+1-0=

Answer 1

Răspuns:

13467

Explicație pas cu pas:

200+199-198+197+196-195+....+5+4-3+2+1-0= ?

200+199+198+197+196+195+....+5+4+3+2+1+0=

= 1+2+3+4+5+.....+200 = (1+200)·200:2 = 201·100 = 20100

198+195+192+.....+3+0 = 3+6+9+.....+192+195+198 =

= (3+198)·[(198-3):3+1]:2 = 201·66:2 = 201·33 = 6633

200+199-198+197+196-195+....+5+4-3+2+1-0= 20100-6633 = 13467