Direction
In each series, look for the degree and direction of change between the numbers. In other words, do the numbers increase or decrease, and by how much-
16.
Look at this series: 80, 10, 70, 15, 60, ... What number should come next?
Answer: A Explanation: This is an alternating addition and subtraction series. In the first pattern, 10 is subtracted from each number to arrive at the next. In the second, 5 is added to each number to arrive at the next.