5 x 3 = 15
2 x 3 = 6
So
2/5 = 6/15
Hope it helps
[tex] \dfrac{2}{5}=\dfrac{?}{15}\\\\15:5=3\to\dfrac{2}{5}=\dfrac{2\cdot3}{5\cdot3}=\dfrac{6}{15}\\\\\boxed{\dfrac{2}{5}=\dfrac{6}{15}} [/tex]
