How many shoppers made a purchase at an online store, a locally-owned store, and a big-box store?

Answer : The number of shoppers made a purchase at an online store, a locally-owned store, and a big-box store is, 18

Step-by-step explanation :

As we are given that:

The number of shoppers made a purchase at big-box store = 17 + 18 + 57 = 92

The number of shoppers made a purchase at online store = 38 + 18 + 57 = 113

The number of shoppers made a purchase at locally owned store = 17 + 18 + 38 = 73

The intersection of big-box store and online store = 57 + 18 = 75

The intersection of big-box store and locally owned store = 17 + 18 = 35

The intersection of locally owned store and online store = 38 + 18 = 56

The intersection of online store, a locally-owned store, and a big-box store = 18

18 is the common number for all the stores.

Thus, the number of shoppers made a purchase at an online store, a locally-owned store, and a big-box store is, 18