No LLM or other modern AI architecture I'm aware of is supposed to model the human brain. Even if they were, LLMs can add large numbers with the level of skill I'd expect from a 10 year old:
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What's 494547645908151+7640745309351279642?
ChatGPT said: The sum of 494,547,645,908,151 and 7,640,745,309,351,279,642 is:
7,641,239,857,997,187,793
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(7,641,239,856,997,187,793 is the correct answer)
I tried it on gpt-4-turbo and it seems to give the right answer:
>Let's calculate:494,547,645,908,151+7,640,745,309,351,279,642=7,641,239,856,997,187,793 >494,547,645,908,151+7,640,745,309,351,279,642=7,641,239,856,997,187,793 >Answer: 7,641,239,856,997,187,793