Answer:
5 days
Step-by-step explanation:
Let N be number of souvenirs bought and D be number of days of vacation.
N is directly proportional to D
N = kD, where k is constant of proportionality.
k = N/D = 6/2 = 3
N = 3D
when N = 15
15 = 3D
Divide both sides by 3
D = 15/3 = 5
Therefore, number of days Clare will have to spend is 5 days