Question

Afla valuarea nr necunoscut din urmatoarele expresii [420:a)×4+24] :4=11 , 402+[1002 : 3-(100+a)×2

Answer 1

[(420:a)×4+24] :4=11
[(420:a)×4+24] = 11×4
(420:a)×4+24 = 44
(420:a)×4 = 44-24
(420:a)×4 = 20
420:a = 20:4
420:a = 5
a = 420:5
a = 84

Verificare:
(5×4+24):4 =( 20+24):4 = 44:4 = 11

402+[1002 : 3-(100+a)×2 ]:4 = 408
[1002:3-(100+a)×2]:4 = 408-402
[334-(100+a)×2]:4 = 6
334-(100+a)×2 = 6×4
334-(100+a)×2 = 24
(100+a)×2 = 334-24
(100+a) ×2= 310
100+a = 310:2
100+a = 155
a = 155-100
a = 55