b si c, va rog.
Mulțumesc!
12 puncte si coroana!
Răspunsuri la întrebare
Răspuns
Explicație pas cu pas:
b)
12 - ( 100 + a × 3 ) : 4 : 8 = 4
( 100 + a × 3 ) : 4 : 8 = 12 - 4
100 + a × 3 = 8 × 8 × 4 → aplic metoda mersului invers
100 + a × 3 = 256
a × 3 = 256 - 100
a × 3 = 156
a = 156 : 3
a = 52
_________________
90 - ( 75 + a + 75 : 5 ) : 13 = 75
( 75 + a + 15 ) : 13 = 90 - 75
( 90 + a ) : 13 = 15
90 + a = 15 × 13
a = 195 - 90
a = 105
_________________________
c)
( a + 26 : 2 ) × 3 + 4 = 97
( a + 13 ) × 3 = 97 - 4
( a + 13 ) × 3 = 93
a + 13 = 93 : 3
a + 13 = 31
a = 31 - 13
a = 18
____________________
a : ( 75 : 5 + 80 : 2 ) + 60 × 4 = 245
a : ( 15 + 40 ) + 240 = 245
a : 55 = 245 - 240
a : 55 = 5
a = 5 × 55
a = 275
________________
d)
128 - ( 175 - a : 8 ) : 8 = 54 × 2
128 - ( 175 - a : 8 ) : 8 = 108
( 175 - a : 8 ) : 8 = 128 - 108
( 175 - a : 8 ) : 8 = 20
175 - a : 8 = 20 × 8
a : 8 = 175 - 160
a : 8 = 15
a = 15 × 8
a = 120
_______________________
( a : 5 + 5 ) × 5 + 5 + 5 × 40 = 150 × 2
( a : 5 + 5 ) × 5 + 5 + 200 = 300
( a : 5 + 5 ) × 5 = 300 - 200 - 5 → aplic metoda mersului invers
( a : 5 + 5 ) × 5 = 95
a : 5 + 5 = 95 : 5
a : 5 + 5 = 19
a : 5 = 19 - 5
a : 5 = 14
a = 14 × 5
a = 70