What is 10-8+6-4+...+(-12)? Choose the correct answer:
A) 8  B) 10  C) 12  D) 14  E) 16
The expression considers all even numbers between 10 and -12 with alternate addition and subtraction of the numbers.   The numbers to be used are: 10, 8, 6, 4, 2, 0, -2, -4, -6, -8, -10, and -12   Now, the first term is positive and the next term is subtracted. So, the required expression becomes,   10 - 8 + 6 - 4 + 2 - 0 + (-2) - (-4) + (-6) - (-8) + (-10) - (-12)   = 10 - 8 + 6 - 4 + 2 - 0 - 2 + 4 - 6 + 8 - 10 + 12   = 42 - 30= 
<gadget id="calculator">42 - 30</gadget>
<output>12</output>
12   Hence the correct answer choice is 12.
<result>C</result>
What is 10-8+6-4+...+(-12)?