Question

at a parade, 1/4 of the participants have red hair, 1/6 of them have brown hair and the rest of them have black hair. which fraction of the participants have black hair?

Answer 1

$\frac{1}{1}-\ all\ participants\\\\ \frac{1}{4}-\ participants\ with\ red\ hair\\\\ \frac{1}{6}-\ participants\ with\ brown\ hair\\\\ participants\ ith\ black\ hair=1-\frac{1}{4}-\frac{1}{6}\ \ \ | mu;tiply\ by\ 12\\\\ 12participants\ ith\ black\ hair=12-3-2\\\\ 12participants\ ith\ black\ hair=7\ \ \ \ | divide\ by\ 12\\\\ participants\ ith\ black\ hair=\frac{7}{12}$