A candy company sells premium chocolate at $5 per pound and regular chocolate at $4 per pound in increment of whole pound only.If Barrett buys a pack of candies which costs him $40, how many pounds of premium chocolates are in the box?  Choose the correct choice from the following choices:
A) [A] 1
B) [B] 2
C) [C] 3
D) [D] 4
E) [E] 5
This question is a bit of Special equations with a single set of unique values.   the Equation stands : 5X + 4Y = 31   Subtract multiple of 5 from 31 and check whether the remaining total is divisible by 4   31 - 5= 
<gadget id="calculator">31 - 5</gadget>
<output>26</output>
26 -&gt; Not divisible by 4   31 - 10= 
<gadget id="calculator">31 - 10</gadget>
<output>21</output>
21 -&gt; Not divisible by 4   31 - 15= 
<gadget id="calculator">31 - 15</gadget>
<output>16</output>
16 -&gt; Divisible by 4   31 - 20= 
<gadget id="calculator">31 - 20</gadget>
<output>11</output>
11 -&gt; Not divisible by 4   31 - 25= 
<gadget id="calculator">31 - 25</gadget>
<output>6</output>
6 -&gt; Not divisible by 4   31 - 30= 
<gadget id="calculator">31 - 30</gadget>
<output>1</output>
1 -&gt; Not divisible by 4   Any multiple of 5 hereon will give a negative value for regular chocolates bought and hence, inadmissible   Thus Amount spent on regular chocolate= $16   Amount spent on Premium chocolate= $15   Price per premium chocolate = $5   No. Of boxes of premium chocolate bought = 20 / 5= 
<gadget id="calculator">20 / 5</gadget>
<output>4</output>
4   Correct Option : [D] 4
<result>D</result>
A candy company sells premium chocolate at $5 per pound and regular chocolate at $4 per pound in increment of whole pound only.If Barrett buys a pack of candies which costs him $40, how many pounds of premium chocolates are in the box?