Find the common difference.
-4. - 20. - . -2, - , - .
Plz help me ?

What is 32+4 x (16 x 1/2) -2 show your work}

The sum of two numbers is 86, and their difference is 20. find the two numbers

For the rule of 78, for a 12-month period, the last term in the sequence is 12 and the series sums to 78. for an 10 month period, the last term is and the series sum is . for a 15 month period, the last term is and the series sum is . for a 20 month period, the last term is and the series sum is