Максим123,
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<title>Untitled</title>
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<span class="price-new" itemprop="price" content="3649.00">3 649.00грн.</span>
<script>
var span = document.querySelector(".price-new"),
content = +span.getAttribute("content"),
google_tag_params = {dynx_totalvalue: content };
alert(google_tag_params.dynx_totalvalue)
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