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?

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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 4.DS.11.a taught?

This standard is part of the Grade 4 curriculum in Virginia Standards of Learning - Mathematics.

Are there practice problems for 4.DS.11.a?

Yes, there are 3 practice problems available for 4.DS.11.a with worked examples.

What learning resources are available for 4.DS.11.a?

There are 1 Khan Academy resources available for 4.DS.11.a, including 1 videos.

4.DS.11.a: Calculate the theoretical probability of random events and compare them to the observed frequencies.

Calculate the theoretical probability of random events and compare them to the observed frequencies.

Example Problems

Yvonne joins a fishing contest. She tracks how many fish each competitor catches in a fixed four-hour window.

Across 200 competitors:

Fish caught	0	1	2	3	4	5
Frequency	60	52	38	28	?	12
Probability	0.3	0.26	0.19	0.14	0.05	0.06

Fill in the missing information to complete the probability distribution.
Do not round your answers.

Will is testing a household robot that must complete three daily chores. He records how many chores the robot fails each day.

Over 100 days:

Failed chores	0	1	2	3
Frequency	45	30	?	5
Probability	0.45	0.3	0.2	0.05

Fill in the missing information to complete the probability distribution.
Do not round your answers.

Aisha practices free throws, shooting sets of four in a row. She records how many shots she makes in each set.

Results for 80 sets:

Shots made	0	1	2	3	4
Frequency	8	20	25	18	9
Probability	0.1	0.25	0.3125	0.225	?

Fill in the blanks to complete the probability distribution.
Do not round your answers.

Khan Academy Resources

Experimental versus theoretical probability simulation

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