What’s the median of this data set ?

56

Step-by-step explanation:

The median is the middle number of a sorted set from least to greatest. After sorting the set 61, 48, 52, 65, 56, 77, 54 the set is 48, 52, 54, 56, 61, 65, 77.

The middle number in this set is 56 so the median is 56

You cannot buy it.

Step-by-step explanation:

$450 with a 20% percent discount would be $360

Add in a sales tax of 5.25%, and it amounts to $549 in total.

Since you only have $400, you cannot buy the bike.