Three containers C_1, C_2 and C_3 have water at different temperatures. The table below shows the final temperature T when different amounts of water…

Three containers $\displaystyle \mathrm{C}_1, \mathrm{C}_2$ and $\displaystyle \mathrm{C}_3$ have water at different temperatures. The table below shows the final temperature T when different amounts of water (given in liters) are taken from each container and mixed (assume no loss of heat during the process)

$\displaystyle \mathrm{C}_1$	$\displaystyle \mathrm{C}_2$	$\displaystyle \mathrm{C}_3$	T
$\displaystyle 1 l$	$\displaystyle 2 l$	--	$\displaystyle 60$°C
-	$\displaystyle 1 l$	$\displaystyle 2 l$	$\displaystyle 30$°C
$\displaystyle 2 l$	--	$\displaystyle 1 l$	$\displaystyle 60$°C
$\displaystyle 1 l$	$\displaystyle 1 l$	$\displaystyle 1 l$	$\displaystyle \theta$

The value of $\displaystyle \theta$ (in $\displaystyle { }^{\circ} \mathrm{C}$ to the nearest integer) is \_\_\_\_.