The local classic car auction raised $12,000 for local charities, the mayor is designating the funds to the children’s hospital. Which sentence error does the text make?
The error is called a comma split. That is because the two clauses are connected with a comma without a conjunction and this is ungrammatical. You should either turn them into two sentences, or add a conjunction, or turn the comma into a semi-colon. This way you would correct the error.