Answer:
a. 18,000
b. $5.10
Explanation:
<u>Calculation of the total equivalent units of production for materials</u>
Units of Closing Work In Process  (6,000× 100%) =  6,000
Units completed and transferred (12,000× 100%) = 12,000
Total                                                                          = 18,000
<u>Calculation of the total equivalent units of production for conversion</u>
Units of Closing Work In Process  (6,000 × 50%) =  3,000
Units completed and transferred (12,000× 100%) = 12,000
Total                                                                          = 15,000
<u>Calculation of Total Cost of Materials</u>
Work in process                      $13,800
Costs added during May       $42,000
Total                                        $55,800
<u>Calculation of Total Cost of Conversion</u>
Work in process                       $ 3,740
Costs added during May       $26,260
Total                                        $30,000
<u>Calculation of total cost per equivalent unit for May</u>
Materials ($55,800/18,000)       = $3.10
Conversion ( $30,000/15,000)  = $2.00
Total                                             = $5.10