In the 30-day month of June, a motorcycle dealership sold a different number of motorcycles each day. If it recorded at least one sale each day, did the dealership sell at least 525 motorcycles during June?
1) The smallest number of motorcycles sold on any one day was 3.
Since number of cycles sold are different on each day, June has 30 days
Least number of cycles sold is 30
Let us consider the least case possible,
3,4,.........33(in 30 days, all consecutive numbers)
n(n+1)/2 => (33(34)/2) -3 = 525
So, in least case it is 525
Sufficient
2) The second highest number of motorcycles sold on any one day was 59.
Since number of cycles sold are different on each day, June has 30 days
Least number of cycles sold is 30
Let us consider the least case possible,
1,2,3,4,.........30(in 30 days, all consecutive numbers)
n(n+1)/2 => (30*(31)/2) = 465
But given second highest is 59 , and Least case highest would be 60
Lets replace 29, 30 we considered as second highest and highest with 59 and 60
465 - 29-30+59+60 = 525
So, in least case it is 525
Sufficient
Option D is correct