September 13 2025 DSAT – Test 9C: Sample Questions & Full Analysis

Expert Breakdown of the September 2025 Digital SAT (Test 9C)

Welcome to the allsatpapers.com expert analysis! As specialists in official test materials, we know that success on the Digital SAT comes from practicing with real, official exams. The 13 September 2025 DSAT (Test 9C) is a key test form from this administration. It provides a crucial look at the types of questions, vocabulary, and mathematical reasoning skills the College Board is currently using to challenge students.

This post will provide a deep dive into this specific test, quoting key passages that customers often search for to identify the exam they need. Let's analyze what makes Test 9C a vital study tool.

Section 1: Reading & Writing Module 1 (Key Passages)

The first R&W module is designed to set your baseline. As requested, we have quoted the first two questions in full, as these are the most common passages users search for to identify this test.

Section 1: Reading & Writing Module 2 (Adaptive) Analysis

This module's difficulty adapts based on your performance in Module 1. The questions become more complex, testing more nuanced vocabulary and text structures. Here are some key passages from Module 2 of Test 9C.

Section 2: Math Module 1 Analysis

The first math module on Test 9C features a standard mix of algebra, data analysis, and geometry. The focus is on foundational skills and straightforward application.

Core Concepts on Display

• Translating to Algebra (Question 1): This question provides an image of an isosceles triangle with sides labeled $x$, $y$, and $y$. It states the perimeter is 63 inches. Your task is to create the equation. The perimeter is the sum of all sides: $x + y + y = 63$, which simplifies to $x + 2y = 63$. This is a direct test of translating a description into an algebraic expression.
• Rates (Question 2): A simple but essential skill. The problem gives a total of 2,070 muskrats in a 115-acre area and asks for the population density. Density is a rate: $\text{Population} / \text{Area}$. The calculation is $2070 / 115 = 18$ muskrat per acre.
• Data Analysis (Question 16): This question asks for the slope of a line of best fit on a scatterplot of Temperature vs. Depth. The line clearly goes down, so the slope is negative. By picking two points on the line, such as (15, 22) and (70, 13), we can estimate the slope: $\text{Slope} = (y_2 - y_1) / (x_2 - x_1) = (13 - 22) / (70 - 15) = -9 / 55$. This decimal is approximately -0.163. The closest answer choice is -0.17.

Section 2: Math Module 2 (Adaptive) Analysis

This module increases the complexity, requiring multi-step problem-solving and a deeper understanding of algebraic structures.

Advanced Applications

• Statistics (Question 1): This question tests the concept of standard deviation by asking which data set has the smallest one. Standard deviation is a measure of "spread." You don't need to calculate it; you need to identify the data set that is the most "clumped together."
  • (A) 83, 83, 85, 87, 87 (Spread: 83-87)
  • (B) 83, 84, 85, 86, 87 (Spread: 83-87)
  • (C) 84, 85, 85, 85, 86 (Spread: 84-86)
  • (D) 82, 83, 85, 87, 88 (Spread: 82-88)

  Set (C) is the most tightly clustered, with three values at the mean (85) and the entire set only spanning from 84 to 86. This set clearly has the smallest standard deviation.

• Multi-Step Geometry (Question 6): This problem combines area formulas.
  1. Find the area of Rectangle X: $24 \text{ mm} \times 7.5 \text{ mm} = 180 \text{ sq mm}$.
  2. We are told this area is 3 times the area of Right Triangle Y. So, $\text{Area(Y)} = 180 / 3 = 60 \text{ sq mm}$.
  3. The formula for a triangle's area is $(\frac{1}{2}) \times \text{base} \times \text{height}$. The base is 60 mm.
  4. $60 = (\frac{1}{2}) \times 60 \times h$
  5. $60 = 30 \times h$
  6. $h = 2 \text{ mm}$.
• Advanced Factoring (Question 16): This question asks which expression is NOT a factor of $1,440x^4 - 56,250$. This requires factoring in multiple stages:
  1. GCF: First, factor out the Greatest Common Factor. Both numbers are divisible by 90. This gives: $90(16x^4 - 625)$. So, (B) 90 is a factor.
  2. Difference of Squares: The binomial $16x^4 - 625$ is a difference of two squares: $(4x^2)^2 - (25)^2$. This factors to $(4x^2 - 25)(4x^2 + 25)$. This means (A) $4x^2 + 25$ is a factor. (Note: choice order may vary).
  3. Difference of Squares (Again): The factor $(4x^2 - 25)$ is also a difference of two squares: $(2x)^2 - (5)^2$. This factors to $(2x - 5)(2x + 5)$. This means (D) $2x + 5$ is a factor.

  The only expression that is not a part of the final factored form is (C) $2x^2 - 5$.

Overall Difficulty and Analysis of Test 9C

After a comprehensive review of all four modules, here is our expert assessment of the 13 September 2025 (9C) DSAT:

• Overall Difficulty: Medium-Hard.
• Analysis: This test is a "form" of the September 13, 2025 exam, meaning it is **content-identical to Tests 9A and 9B**. The passages, questions, and even the data in the graphs are the same. The only difference is the order of the answer choices. This is a standard College Board practice to create multiple test "forms" and prevent cheating.
• Reading & Writing: The section is of **Medium** difficulty. It heavily tests "Words in Context" where the clue is embedded in the surrounding text. Module 2 appropriately raises the difficulty with more complex vocabulary (like "proxies for") and more nuanced text-structure questions.
• Math: This section is **Medium-Hard**. Module 1 is a straightforward review of foundational algebra and data analysis. Module 2, however, contains a significant difficulty spike with complex, multi-step problems designed to differentiate high-scoring students. The advanced factoring question (M2 Q16) and the multi-step geometry problem (M2 Q6) are prime examples of this.

Why This Practice Test is Essential For Your Prep

DSAT Test 9C (13 September 2025) is a perfect snapshot of the current Digital SAT. It clearly shows the test's emphasis on:

• Vocabulary in Context: You must be able to use contextual clues to determine the precise meaning and function of a word.
• Evidence-Based Reading: The ability to read a short passage or graph and find the one piece of evidence that directly supports a claim is critical.
• Algebraic Fluency: The Math section is dominated by algebra. Fluency in factoring, solving linear equations, and setting up inequalities from word problems is non-negotiable.
• Multi-Step Problem Solving: The hardest questions (like the factoring and geometry problems in Module 2) are not testing obscure concepts. They are testing your ability to execute multiple foundational concepts in the correct order.

Studying with an official past paper like Test 9C is the single best way to build the skills and pattern recognition needed to excel on test day. Analyzing your mistakes on this exam will show you exactly what to focus on in your remaining prep time.