Răspuns
Explicație pas cu pas:
1. Notez cu ,,m" = numar mere si cu ,,p" = numar prune"
p = 4 x m
p - 4 = 7 x ( m - 4 ) ⇒ p = 7 × m - 28 + 4 ⇒ p = 7 × m - 24
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7 × m - 24 = 4 × m → numarul prunelor
7 × m - 4 × m = 24
3 × m = 24
m = 24 : 3
m = 8 ( mere )
4 × 8 = 32 prune
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Verific: 32 - 4 = 7 x ( 8 - 4 )
28 = 7 x 4 ( corect )
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2)
a : b = 5 rest 13 ⇒ a = 5 x b + 13
a + b = 469
( 5 x b + 13 ) + b = 469
6 x b = 469 - 13
6 x b = 456
b = 456 : 6 ⇒ b = 76
a = 469 - 76 ⇒ a = 393