A forester wants to plant 44 apples tree, 66 banana trees and 110 mango trees in equal rows (in terms of number of trees). Also, he wants to make distinct rows of tree (i.e. only one type of tree in one row). The number of rows (minimum) that required is:

$$\eqalign{ & {\text{In}}\,{\text{such}}\,{\text{case}},\, \cr & {\text{we}}\,{\text{first}}\,{\text{need}}\,{\text{to}}\,{\text{find}}\,{\text{the}}\,{\text{HCF}}\,{\text{of}}\,{\text{44,66,110}}. \cr & 44 = 2 \times 2 \times 11 \cr & 66 = 2 \times 3 \times 11 \cr & 110 = 2 \times 5 \times 11 \cr & {\text{HCF}} = 2 \times 11 = 22 \cr & {\text{Then,}}\,{\text{the}}\,{\text{required}}\,{\text{numbers}}\,{\text{of}}\,{\text{rows}}, \cr & = { {\frac{{44}}{{22}}} + {\frac{{66}}{{22}}} + {\frac{{110}}{{22}}} } \cr & = 10 \cr} $$