Concursul "Congruente", problema 1

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Claudiu Mindrila
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Concursul "Congruente", problema 1

Post by Claudiu Mindrila »

Cate numere cuprinse intre \( 100 \) si \( 801 \) se impart exact la \( 8 \)?
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naruto
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Post by naruto »

\( 100 < 8k < 801 \)

\( 100=8\cdot 12+4 \)
\( 801=8\cdot 100+1
\)

Rezulta \( 8k \in \{8\cdot 13, 8\cdot 14,........,8\cdot 100\} \).

\( 100-13+1=88 \). Raspuns: \( \overline{ \underline{|\ 88 \ \mbox numere\ |} } \)
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Dorobantu Razvan
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Post by Dorobantu Razvan »

intre 100 si 801 sunt cuprinse 700 nr.
primul care se imparte la 8 este 104, iar ultimul 800
intre acestea sunt cuprinse 697 nr. (inclusiv 104 si 800)
697:8=87(rest 1)
87+1=88 nr.
E bine? :?: :?
Marcelina Popa
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Post by Marcelina Popa »

Da, e corect :).
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