Question

1) Efectuati,dand factor comun:
a) 38 * 37 + 38 * 63
b) 86 * 53 - 76 * 53
c) 47 * 99 + 47
d) 47 * 61 - 47
e) 2012 * 2011 + 2012 * 2013 - 2012 * 4024

2) Determinati numarul natural m pentru care are loc egalitatea :
{ 13 + [ 25 * 4 - ( 3 * 11 + 3 * 22 ) ] * m } : 2 = 13

3) Aflati numarul natural a care verifica relatia { [ ( a : 2 ) + a ] : 3 } : 4 = 10

4) Calculati diferenta dintre cel mai mic numar natural de cinci cifre diferite doua cate doua si cel mai mare numar natural de patru cifre diferite de doua cate doua.

Answer 1

1)
a)38x(37+63)=
38x100=3800

b)53x(86-76)=
53x10=530

c)47x99+47=
4653+474700

d)47x61-47=
2867-47=2820

e)2012x(2011+2013)-2012x4024=
8096288-2096288=0

2)13+[25x4-(33+66)]xm=13x2=26
13+(25x4-99)xm=26
13+(100-99)xm=26
13+1xm=26
1xm=26-13
1xm=13
,=13:1
m=13

3){[(a:2)+a]:3}:4=
(a:2)+a=10x4x3=120

a:2+a=120/x2
a+2a=240
a=240:3
a=80