I dont understand how we go from effective annual to effectuve monthly...... i would of though you divide by 12 but no matter what formula i use, i cant seem to get the same answer as in the problem, thank you for your help

Example: 12.3 What is the accumulated value following the last payment of $100 deposited at the end of each month for 30 years into an account that earns an effective annual rate of 10%? Use calc to find j = % = 0.7974 effective per month 12 AV = 100 36011 S - ) 206,284