A company sells a product for $6.4 per unit. Fixed expenses total $37.9k per month and variable expenses are $2.6 per unit. Calculate the number of units that must be sold each month to realize a profit of 15.16% of sales.

Note: The term k is used to represent thousands ( $1,000).

Answer k (INPUT YOUR ANSWER IN K, ROUNDED TO 3 DECIMAL PLACES. FOR EXAMPLE: 7.321)