Question

Afla valoarea nr a daca:
a+29=b
b:4=c
c×5=d
d-30=15

Answer 1

a+29=b a+29=36 a=36-29 a=7
b:4=c b:4=9 b=4x9 b=36
cx5=d 5c=45 c=45:5 c=9
d-30=15 d=15+30 d=45

Answer 2

     a+29=b
     b:4=c
     5c=d
     d-30=15
 ------------------------
   d=5c
 =>d-30=15
=>5c-30=15
=>5c=15+30
=>5c=45
=>c=45/5
=>c=9
-----------------------
b:4=9
b=9*4
b=36
------------------------

c*5=d
9*5=d
9*5=45
=>d=45
------------------------

a+29=36
a=36-29
a=7
--------------------
Proba:7+29=36
          36:4=9
          9*5=45
          45-30=15