wpf radiobutton IsChecked problem

Hi,

I am new at WPF.

I need the answer of this,

I have two radio buttons and their bindings like 

<RadioButton Style="{DynamicResource MyCss}" IsChecked="{Binding Place.ToColour,Mode=TwoWay}"  Grid.Column="1">Red</RadioButton>

<RadioButton Style="{DynamicResource MyCss}" IsChecked="{Binding Place.ToColour,Mode=TwoWay}"  Grid.Column="2">Yellow</RadioButton>

If the binding value Place.ToColor is 1 then first radio should come cheked otherwise the other.

how can I manage that with a converter .

Any help will be appreciated.

thanks in advance