Is Goblins free for teachers?

Yes. Goblins offers a generous free tier that includes 1 live feedback assignment per week, insights on student mastery and replays, and the ability to upload your own content. The Max plan adds unlimited assignments, superadaptive mode, grade exports, standards growth reports, and SSO/LMS integration, with per-student pricing for schools and districts.

How does Goblins work?

Three simple steps: (1) Share an assignment from thousands of standards-aligned topics using a share code. (2) Students speak and draw their thinking naturally, and Goblins responds with Socratic questioning that sounds just like their teacher. (3) Teachers get real-time formative insights showing what students struggle with and suggestions to inform instruction.

Does Goblins prevent cheating?

Yes. Goblins uses a purpose-trained AI model that evaluates cheating signals in real time. It can detect when students are copying answers, using external tools inappropriately, or not genuinely working through problems. Copy-pasting answers is also blocked.

Can I use my own voice with Goblins?

Yes. Teachers can record their voice and take a selfie to create a custom 3D avatar in about 30 seconds. Students then hear help in their own teacher's voice and see a familiar face, making the experience more personal and effective.

What math levels does Goblins cover?

Goblins covers math from Grade 5 through AP Calculus, including thousands of standards-aligned topics. Teachers can also upload their own content for custom assignments at any level.

Is Goblins FERPA compliant?

Yes. Goblins is FERPA and state compliant. Student data privacy and security are a top priority.

Does Goblins support English Language Learners?

Yes. Goblins supports 30+ languages so teachers don't have to translate every worksheet. It is especially helpful for ELL students who need accessible math instruction in their native language.

What grade level is SR taught?

This standard is part of the SR curriculum in Georgia Standards of Excellence - Mathematics.

SR: Statistical Reasoning

Statistical Reasoning

Print

SR.DSRSR.DSR SR.DSRaData & Statistical Reasoning – Formulate Statistical Investigative Questions SR.DSRbData & Statistical Reasoning – Collect Data SR.DSRcData & Statistical Reasoning – Analyze Data SR.DSRdData & Statistical Reasoning – Interpret Results SR.MMMathematical Modeling

Example Problems

What is the critical value

t^{*}

for constructing a 90% confidence interval for a mean with 18 degrees of freedom?

Priya was testing

H_0: \mu = 20

versus

H_a: \mu < 20

with a sample of 12 observations. Her test statistic was

t = -2.228

. Assume that the conditions for inference were met.

What is the approximate P-value for Priya's test?
Round your answer to the nearest thousandth.

Identify any outliers from the following table:

Data Value
84
7
9
8

A smartphone manufacturer claims an average battery life of 10 hours on a standard test. A reviewer tests a random sample of 49 phones and finds a sample mean battery life of 9.3 hours with a sample standard deviation of 1.4 hours.

The reviewer wants to use these sample data to conduct a t test on the mean. Assume that all conditions for inference have been met.

Calculate the test statistic for their test.

Three office buildings surveyed a random sample of employees about their recycling habits. Here are the results:

Building	Always	Sometimes	Never	Total
Building A	50	20	10	80
Building B	40	30	10	80
Building C	30	25	15	70
Total	120	75	35	230

They want to perform a χ² test of homogeneity on these results.

What is the expected count for the cell corresponding to Building B employees who never recycle?
Round your answer to the nearest hundredth.

1-on-1 AI tutoring aligned to SR. Instant help for students, real-time insights for teachers.

Used in classrooms by 100,000+ students at Baltimore County, Plano ISD, Deer Valley USD, KIPP, and districts nationwide.

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