arithmetic/geometric/exponential

There are many types of patterns in math. Patterns are sequences of numbers. Often, questions arise on national tests about increases and decreases and show sequences. Here are three types: arithmetic sequence involving adding or subtracting, geometric sequence involving multiplying or dividing, and one more.

I list the type, examples, and solution.

Arithmetic
1, 3, 5, 7, 9...
Add 2 each time.

99, 90, 81, 72...
Subtract 9 each time.

Geometric
1, 2, 4, 8, 16...
Multiply the previous number by 2.

1000, 100, 10, 1...
Divide the previous number by 10.

Exponential
2, 4, 16, 256...
Square the previous number.

1, 4, 9, 16, 25...
Square of 1, 2, 3, 4, 5

These types of problems appear in a variety of questions on national tests, often about population growth.