Answer :
So we can write this our as a mathamatical equation like so 15x=109 just divide both sides by 15 and theres your answer x=7.27 so she would have to mow the lawn 8 times in order to gain the money needed to buy that dress
Shes will have to mow the lawn at least 7 times.109 divded by 15 equals 7.2.So at least 7 times