IB MYP 2 Mathematics || Summative Assessment || Topic: Expressions & Algebraic Sequences || Criteria A & B

IB MYP 2 Mathematics

Summative Assessment – Algebraic Expressions & Sequences

Instructions

• You have 60 minutes to complete this assessment.
• Show all your working clearly and explain your thinking using correct mathematical language, symbols, and steps.
• Use full sentences when describing patterns, rules, or calculations.
• This task assesses both Criterion A (Knowing and Understanding) and Criterion B (Expression).

Part A – Criterion A: Knowing and Understanding

1. Definitions and Understanding:
   In your own words, define the following and provide one numerical example for each:
   • Arithmetic Sequence
   • Geometric Sequence
   • Algebraic Expression
   • Term-to-Term Rule
2. Identifying Sequences:
   For each sequence below, state whether it is arithmetic, geometric, or neither, and explain your reasoning:
   • 2, 5, 8, 11, …
   • 3, 6, 12, 24, …
   • 1, 2, 4, 8, 16, 31, …
3. Finding the nth Term:
   For the sequences identified as arithmetic or geometric above, write an algebraic expression for the \(n^{th}\) term.

Part B – Criterion B: Expression

1. Simplifying Expressions:
   Simplify the following expressions step by step:
   • \( 4x + 7x - 5 \)
   • \( 3(a + 5) + 2a \)
   • \( 6y - 2(3y - 4) \)
2. Applying Sequences:
   Using the algebraic expressions you wrote for the nth term in Part A:
   • Find the 10th term of the arithmetic sequence: 2, 5, 8, 11, …
   • Find the 6th term of the geometric sequence: 3, 6, 12, 24, …
3. Explaining Reasoning:
   For at least one arithmetic and one geometric sequence, explain:
   • How you determined the sequence type
   • How you derived the nth term formula
   • How you used the formula to calculate a specific term
4. Create Your Own Sequence and Expression:
   Write an arithmetic or geometric sequence of at least 5 terms. Then:
   • Describe the rule in words
   • Write the nth term formula
   • Find the 7th term using your formula

Rubrics

Criterion A – Knowing and Understanding

Level	Description
0	The student does not reach a standard described by any of the descriptors below.
1–2	Limited understanding of mathematical concepts and sequences; explanations are mostly unclear.
3–4	Some understanding of concepts; explanations are partially correct and sometimes clear.
5–6	Good understanding of concepts; explanations are mostly correct and clear.
7–8	Thorough understanding of concepts; explanations are clear, precise, and detailed.

Criterion B – Expression

Level	Description
0	The student does not reach a standard described by any of the descriptors below.
1–2	Communicates mathematical ideas with limited clarity; little use of correct notation or reasoning.
3–4	Communicates ideas with some clarity; some correct use of notation and reasoning.
5–6	Mathematical ideas are clearly expressed; reasoning is mostly logical and notation is mostly correct.
7–8	Mathematical ideas are communicated effectively and coherently; reasoning is logical and detailed with consistent correct notation.