In 7500 iPhones, 18 were found defective.
18 of 7500 is 0.24%
0.24% of iPhones were defective.
Using the information above:
In a sample of 60000 new iPhones, 144 would be found defective.
144 of 60000 is 0.24%
Answer: 144 defective iPhones would be expected in a sample of 60,000.
Hope this helps! Good luck. :-)