Question

afla numerele necunoscute.
300-8*a-56=100;
5y+36*4+36*3+36*2=504;
a:20-361-209-55:5-49=90.
2. Efectuează.
a) [(50:10+25)+25]:5=
b)793+200:10-[76+(293-209)]=
c) [(4:4+4):5+9]*22=
d) 769-286-[(279+8):7-3]+250*2=
e) 25+{750+25*[55*5-(165-50:2)]}-50=
f) {76+[(26*26+76)*2]-128}:3=
va rog ajutatima.

Answer 1

1. 300- 8*a - 56 = 100
300 - 8* a = 100+ 56
300 - 8*a = 156
8*a = 300 + 156
8*a = 456
a = 456 : 8 => a = 57 

2. 5y + 36 *4+ 36*3+36*2 = 504
5y + 144 + 108+ 72 = 504
5y + 144 +108 = 504 - 72
5y + 144 +108 =432
5y + 144 = 432 - 108 
5y +144 =  324
5y =324 - 144
5y =180
y = 180 : 5 =>y = 36

3. a:20 - 361 - 209 - 55 : 5 - 49 = 90
a:20-361 - 209 - 11 - 49 = 90
a: 20 -361 -209-11 = 90+49
a:20 - 361 -209 -11 = 139
a:20- 361 - 209 =139+11
a: 20 -361-209 = 150
a: 20 - 361 = 150+ 209
a: 20 -361= 359
a : 20=359+361
a: 20 = 720
a= 720*20 => 14.400

a) [(50:10 + 25) +25]: 5 =
(30+25 ) : 5= 55 : 5 = 11