Answer: 0.71
Explanation:
Older than 50: 50-60 and >=60
50-60 : 90 customers
>=60 : 52 customers
90+52=142 customers
Younger than 30: <20 and 20-30
<20 : 67 customers
20-30: 100 customers
67+100=167 customers
142+167=309 customers are either older than 50 or younger than 30
Total customers:
67+100+55+72+90+52=
167+127+142=
294+142=434 customers
309/434=0.71