<p>As per the given figure, two plates A and B of thermal conductivity K and 2 K are joined together to form a compound plate. The thickness of plates are 4.0 cm and 2.5 cm respectively and the area of cross-section is 120 <span class="equation">\(cm^2 \)</span>for each plate. The equivalent thermal conductivity of the compound plate is&nbsp;<span class="equation">\((1+\frac{5}{\alpha})K\)</span>, then the value of&nbsp;<span class="equation">\(\alpha\)</span>&nbsp;will be_____</p>

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