On your TI-84 calculator,
Press stat
Press the right arrow key to highlight TESTS
Use the down arrow key to scroll down to A:1-PropZint
Press enter
1-PropZInt
x:0.48*500 <--Press the down arrow, it will change to x:240
n:500 <--Press the down arrow
C-Level:0.95 <--Press the down arrow
Calculate <--Press enter
1-PropZint
(0.43621,0.52379)
p=0.48
n=500
The answer is (0.43621,0.52379) or 0.43621 < p < 0.52379
Round off as your teacher told you.
Edwin