Question

Opt mere cantaresc cat 10 pere, 6 pere cantaresc cat 14 piersici, iar 10 piersici cantaresc cat 16 nuci. Daca pe un taler al unei balante asezma 3 mere, cate nuci trebuie sa asezam pe celalalt taler pentru ca balanta sa fie in echilibru.

Answer 1

Răspuns:  3 mere cantaresc cat 14 nuci

Explicație pas cu pas:

8 mere ...... 10 pere [ : 2

6 pere ..... 14 piersici [ : 2

10 piersici...16 nuci  [ : 2     impart relatiile la 2

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4 mere.... 5 pere         si  3 pere ..... 7 piersici      si    5 piersici ... 8 nuci  

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4 mere ... 5 pere [ × 3

12 mere ...15 pere

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dar 3 pere .. 7 piersici [× 5

    15 pere ....35 piersici

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dar 5 piersici ...... 8 nuci   [ × 7

    35 piersici ..... 56 nuci

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Deduc:

12 mere ....... 15 pere .......35 piersici ......... 56 nuci

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Regula de trei simpla

12 mere ............ 56 nuci

 3 mere ...........   x nuci

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x = ( 3×56)/12 = 14

3 mere cantaresc cat 14 nuci

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Sau:  

(8+4)mere.... (10+5)pere .....(14+14+7)piesici .....(3×16+8)nuci

12 mere ....... 15 pere ..........35 piersici .........56 nuci

12 mere ..........56 nuci

6 mere ..........28 nuci [ : 2

3 mere ......... 14 nuci