Respuesta :

Price of DVD player ≥ $150
Saved = $80
Amount needed = $150 - $80 = $70
Saving per week = $10

Let x be the number of weeks needed:
80 + 10x ≥ 150
10x ≥ 150 - 80
10x ≥ 70
x ≥ 70 ÷ 10 
x ≥ 7

Answer: She needs to save for for at least 7 weeks.