Răspuns :
Răspuns:
Explicație pas cu pas:
14.
Notatie:
c - chifle
p - paine
7 * c + 10 * p = 310
5 * c + 12 *p = 270
______________
c= ?, p = ?
______________
5 * c + 12 *p = 270 | * 7
7 * c + 10 * p = 310 | * 5
35 * c + 84 * p = 1890
35 * c + 50 * p = 1550
________________ (-)
/ 34 * p = 340
p = 340 : 34
p = 10 (paini intr-o ladita)
7 * c + 10 * p = 310
7 * c + 10 * 10 = 310
7 * c + 100 = 310
7 * c = 310 - 100
7 * c = 310
c = 210 : 7
c = 30 (chifle intr-o ladita)
15.
Notatie:
p - puzzle mic
r - puzzle mare
7 * p + 6 * r = 1240 piese
6 * p + 7 * r = 1360 piese
___________________
p = ?, r = ?
___________________
6 * p + 7 * r = 1360 | *7
7 * p + 6 * r = 1240 | * 6
42 * p + 49 * r = 9520
42 * p + 36 * r = 7440
_________________(-)
/ 13 * r = 2080
r = 160 (piese puzzle mare)
7 * p + 6 * r = 1240
7 * p + 6 * 160 = 1240
7 * p + 960 = 1240
7 * p = 1240 - 960
7 * p = 280
p = 280 : 7
p = 40 (piese puzzle mic)
16.
Notatie:
s - sticla
b - bidoane
14 * s + 6 * b = 64 litri
10 * s + 7 * b = 62 litri
_________________
s = ?, b = ?
_________________
14 * s + 6 * b = 64 | *7
10 * s + 7 * b = 62 | *6
98 * s + 42 * b = 448
60 * s + 42 * b = 372
________________(-)
38 * s / = 76
s = 76 : 38
s = 2 (sticle)
14 * s + 6 * b = 64
14 * 2 + 6 * b = 64
28 + 6* b = 64
6 * b = 64 - 28
6 * b = 36
b = 36 : 6
b = 6