$\displaystyle P = \sum_{x = 1}^5 \left[ \left( \dfrac{1}{2} \right)^x \left( \dfrac{1}{2} \right)^{5 - x} ({^5}C_x) \right]$

$P = \dfrac{31}{32}$ ← *answer*

**Preferred Solution**

$P = 1 - Q_{\text{all are girls}} = 1 - \left( \dfrac{1}{2} \right)^5$

$P = \dfrac{31}{32}$ ← *answer*