variable embedded on a string

hi, i have a problem with inserting a variable embedded on a string.

The string is formed by two "%" at start and end wich i don't know this
usage (is a part of view_helper.rb of the plugin will_paginate):

%{ view <strong>%d&nbsp;-&nbsp; %d</strong> of <strong>%d</strong>
totals} %

i want to modify in:

%{ #{I18n.t('.mytranslation')} <strong>%d&nbsp;-&nbsp; %d</strong>
#{I18n.t('.mytranslation')} <strong>%d</strong>
#{I18n.t('.mytranslation')} } %

but don' t work.
waht is the correct syntax for this string?