Do account receivable need to plus with net income to get net account receivable?

No, Accounts Receivable is not added to net anything. Net income is the "net" amount of all income. Accounts receivable is not considered "INCOME" until it is actually "received". Net income is something you've already received, not something you will receive in the future (as is accounts receivable).

Net Receivables is defined as: The total money owed to a company by its customers, minus the money owed that will likely never be paid. Net receivables are often expressed as a percentage; the higher the percentage, the more money a company is able to collect from its customers and the better off the company is.

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The Equation is Account Receivables - Allowance for Bad Debts