Question 1044239
Set up a ratio.
340 is to 10 as X is to 12.
{{{340/10=X/12}}}
{{{X=(12/10)340}}}
{{{X=(6/5)340}}}
{{{X=408}}}
So this is the rate for 12 hrs. 
Since there are 2 12 hours in 24 hours or 1 day, the rate for one day would be double the rate of 12 hours,
{{{R[24]=2*408}}}
{{{R[24]=816}}}