Hich expression does not belong with the other three? $\sqrt{16x}+y$

$\frac{3}{5}m+4n$

$a+\frac{4}{7}b$

1foot = 12 inches; 1 yard = 3 feet

Mr and mrs smith buy tickets for themselves and their four children. the cost of an adult ticket is ? 6 more than the adult ticket. the total cost of the six tickets is ? 40.50 work out the cost of an adult ticket. in your working let c be the cost of the child ticket and a be the cost of the adult ticket.

Find the area of an equilateral triangle with a side of 6 inches