Answer:
$5903.39
Explanation:
This can be solve using compound interest formula. The formula is:

Where
F is the future amount (what we are looking for)
P is the present amount (which is 4800)
r is the rate of compound interest per year, in decimal (3% per year, 3/100 = 0.03)
t is the time in years ( t = 7)
Now we substitute these values into the formula and find F:

So, Colin would have $5903.39 after 7 years, in his account.