Question

In gradina au răsărit lalele si narcise in total 27.numarul narciselor este cu 7 mai mare decat numarul laleleor.cate flori de fiecare fel sunt?

Answer 1

notez : l - lalele
n-narcise
lalele+narcise=27
n=l+7
l+l+7=27
2l=20
l=20:2
l=10 ( deci avem 10 lalele )
n=10+7
n=17 ( avem 17 narcise)
Proba: 17 narcise + 10 lalele =27

Answer 2

l + n = 27
n = l + 7

l |____|
n |____|+7

27 - 7 = 20
20 : 2 = 10 (un segment egal)
l = 10 (lalele)
n = 10+7 = 17 (narcise)

verificare:
10 + 17 = 27