It’s the end of the month and it’s time for us to review what we have learned this month. First, we have discussed about arithmetic and geometric sequences and their sums. We have also talked about the areas of parallelograms and trapezoids. Finally, we have a guest post from Patrick Vennebush, the author of *Math Jokes 4 Mathy Folks*, a collection of more than 400 math jokes.

The post this month is listed below in terms of popularity or the total number of shares.

**Month in Review
**

- Deriving the Formula of the Arithmetic Sequence
- The Sum of the First n Positive Integers
- Deriving the Sum of the Arithmetic Sequence
- Derivation of the Area of a Parallelogram
- Making Connection Between Areas of Trapezoids and Parallelograms
- Proofs and Jokes Have a Lot in Common
- Sum of the First n Positive Integers: Another Solution
- Deriving the Sum of the Geometric Sequence
- Derivation of the Area of a Trapezoid

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