Answer:
Lewis spent £14.82.
Explanation:
Total number of cartons of juice Lewis bought = 38
i. If 1 carton of juice = 45 p, then;
Lewis would spend = 38 x 45 p
 = 1710 p
Since 100 p = £1, then;
1710 p = 

 = £17.10
Lewis would have spent £17.10.
ii. If 4 cartons = £1.56, then;
 = 9.5
Lewis would have spent = £1.56 x 9.5
 = £14.82
Given that he bought the cartons of juice for the least possible amount. Thus, Lewis spent £14.82.