Question

Se considera numerele naturale a,b,c
a)Daca a-b=215 si b-c=132 determinati a-c
b)Daca a-c=138 si b-c=129 calculati a-b
c)Daca a-b=72 si (a-c)-(b+c)=18 aflatil pe c
Vreau si explicatie la ele!!Dau coroana!!

Answer 1

a)  

( a - b ) + ( b - c ) = 215 + 132

a - b + b - c = 347

a - c = 347

_______________________

b)

( a - c ) - ( b - c ) = 138 - 129

a - c - b + c = 9

a - b = 9

_____________________________

c)

( a - c ) - ( b + c ) = 18

a - c - b - c = 18

( a - b ) - 2 c = 18

72 - 2 c = 18

2 c = 72 - 18

2 c = 54

c = 54 : 2

c = 27