Girls are 3 equal units = 21. Boys are $$\frac{2}{3}$$ of the girls, so 2 of those units.<br><br>[[model:questions/solutions/q3428.png]]<br><br>• Girls = 3 units → 21<br>• 1 unit → 21 ÷ 3 = 7<br>• Boys = 2 units → 2 × 7 = 14<br><br>There are 14 boys.<br>Check: $$\frac{2}{3}$$ of 21 = 14. ✓