If a, b, c, and d are integers; w, x, y, and z are prime numbers; w < x < y < z; and (wa)(xb)(yc)(zd)=660(wa)(xb)(yc)(zd)=660, what is the value of (a + b) – (c + d)?
Choose the most appropriate option.
A) –1 B) 0 C) (a + b) – (c + d)=1 D) 2 E) 3
660660= 2^2 x 3^1 x 5^1 x 11^1   w &lt; x &lt; y &lt; z = 2 &lt; 3 &lt; 5 &lt; 11   So, can can say -   w = 2   x = 3   y = 5   z = 11   Hence a = 2 , b = c = d = 1   (a + b) – (c + d) will be (2 + 1) – (1 + 1) = 1   Answer will be ((a + b) – (c + d)=1)
<result>C</result>
If a, b, c, and d are integers; w, x, y, and z are prime numbers; w < x < y < z; and (wa)(xb)(yc)(zd)=660(wa)(xb)(yc)(zd)=660, what is the value of (a + b) – (c + d)?