Iris is a saleswoman whose base pay plus commissions amounted to $69,464 last year. if her base pay was $39,710 and she made $78,300 in sales last year, what was her rate of commission? a. 51% b. 38% c. 57% d. 89%

Iris is a saleswoman whose base pay plus commissions amounted to $69,464 last year. If her base pay was $39,710 and she made $78,300 in sales last year, 
what was her rate of commission? 
Commissions were $29,590 against sales of $78,300 
Her rate of commission was 37.79%