Incorrect. Filling in the chart will help obtain the equation you need to find the answer:

	Acidity		Amount of sol. (liters)		Amount of acid (liters)
Sol. 1	10%	*	$\displaystyle{x}\usepackage{cmbright}\Huge\$	=	$\displaystyle{0.10}{\left({x}\right)}\usepackage{cmbright}\Huge\$
Sol. 2	40%	*	$\displaystyle{40}-{x}\usepackage{cmbright}\Huge\$	=	$\displaystyle{0.4}{\left({40}-{x}\right)}\usepackage{cmbright}\Huge\$
Mix	20%	*	40	=	8

This gives you an equation of: $\displaystyle{0.1}{\left({x}\right)}+{0.4}{\left({40}-{x}\right)}={8}\usepackage{cmbright}\Huge\$ . When you solve for x, look back to the chart to see that x represents the amount of liters of solution 1 you will need. Subtract to find the amount of liters of solution 2 you will need.