7 and 14 are both multiplies
120 days is approximately equals to 4 months. (30 days * 4 = 120 days)
Now you deposited 7000 dollars at 6.5% interests.
IN 1 months
=> 7000 * .065 = 455 dollars in 1 month is the interest
=> 455 * 4 months = 1820 dollars n 4 months
=> 7000 + <span>1820 = 8820 dollars.</span>
At the end of the first year, the correct formula is this one:

The second year, we add r times the above amount, we get:

Iterating the process, we get the general formula of any number of years:
10 bronze medals
explaining:
if 3 of the medals were gold there would be 15 left. Since there was twice as many bronze from silver they would have 5 silver medals and 10 bronze.