Question

Un aranjament floral compus din 6 trandafiri si 3 crini costa 78 de lei,iar altul,compus din 3 trandafiri si 5 crini costa 93 de lei. Afla cat costa un trandafir si cat costa un crin

Answer 1

6 trandafiri........3 crini.........78 lei
3 trandafiri........5 crini........93 lei /×2


6 trandafiri........3 crini.........78 lei
6 trandafiri.......10 crini........186 lei
__________________________
/ ...................7 crini.........108 lei
1 crin=108:7
1 crin=15,42 lei

6 trandafiri........3 crini.........78 lei
1 crin=15,42 lei
inlocuim.....
6 trandafiri+3×15,42=78
6 trandafiri+46,26=78
6 trandafiri=78-46,26
6 trandafiri=31,74
1 trandafir=31,74:6
1 trandafir=5,29 lei

verificare:
6 trandafiri........3 crini.........78 lei
1 crin=15,42 lei
1 trandafir=5,29 lei
inlocuim.....
6 × 5,29 + 3 × 15,42 = 78
31,74 + 46,26 = 78
78=78 (adevărat)