How do I come up with the value: 20 for the adjusted journal entry for question12. What does "supplies counted" mean, how does that 10 convert to 20?

Brothers Harry and Herman Hausyerday began operations of their machine shop (H & January 1, 2013. The annual reporting period ends December 31. The trial balance on follows (the amounts are rounded to thousands of dollars to simplify) Account Titles Cash Accounts Receivable Supplies Land Equipment Accumulated Depreciation Software Accumulated Amortization Accounts Payable Notes Payable (short-term) Salaries and Wages Payable Interest Payable Income Tax Payable Common Stock Retained Earnings Service Revenue Salaries and Wages Expense Depreciation Expense Amortization Expense Income Tax Expense Interest Expense Supplies Expense Debit Credit 12 60 15 71 Totals $ 95 $ 95 Transactions during 2015 (summarized in thousands of dollars) follow: 1. Borrowed $12 cash on March 1 using a short-term note 2. Purchased land on March 2 for future building site; paid cash, $9 3. Issued additional shares of common stock on April 3 for $23 4. Purchased software on July 4, $10 cash 5. Purchased supplies on account on October 5 for future use, $18 6. Paid accounts payable on November 6, $13 7. Signed a $25 service contract on November 7 to start February 1, 2016 8. Recorded revenues of $160 on December 8, including $40 on credit and $120 collected in cash 9. Recognized salaries and wages expense on December 9, $85 paid in cash 10.Collected accounts receivable on December 10, $24 Data for adjusting journal entries as of December 31 11. Unrecorded amortization for the year on software, $5 12. Supplies counted on December 31, 2015, $10 13.Depreciation for the year on the equipment, $6 14. Interest of $1 to accrue on notes payable 15. Salaries and wages earned but not yet paid or recorded, $12 16.Income tax for the year was $8. It will be paid in 2016