Răspuns:
Explicație pas cu pas:
(a + 49 ) : 9 = 37 rest 6
a + 49 = 37 × 9 + 6
a + 49 = 333 + 6
a + 49 = 339
a = 339 - 49
a = 290
_____________________
930 : ( a - 13 ) = 9 rest 3
a - 13 = ( 930 - 3 ) : 9
a - 13 = 927 : 9
a - 13 = 103
a = 103 + 13
a = 116
_______________________
[ 428 : ( a - 28 ) - 25 x 3 ] x 8 = 256
428 : ( a - 28 ) - 75 = 256 : 8
428 : ( a - 28 ) - 75 = 32
428 : ( a - 28 ) = 32 + 75
428 : ( a - 28 ) = 107
a - 28 = 428 : 107
a - 28 = 4
a = 4 + 28
a = 32
___________________________
( a x 2 + 12 ) : 4 = 88 rest 2
a × 2 + 12 = 88 × 4 + 2
a × 2 + 12 = 352 + 2
a × 2 = 354 - 12
a × 2 = 342
a = 342 : 2
a = 171
