Answer:
In 6/ 12 hours they will be the same.
We have the slope m = (6-3)/(4-1) = 3/3 = 1;
Then, y - 3 = 1·( x - 1);
finally, y = x + 2.
107360 yards = 31 miles = 1 hour
1 second = 1789.3333333 yards
This is a compound interest problem so you cannot use the simple interest formula. Effectively the total amount is being compounded each year by 6%. There is a formula for compound interest but in this simple example you can work this out recursively.
year 1 = 6500
year2 = 6500*1.06 = 6890
year3 = 6890*1.06 = 7303
year4 = 7303*1.06 = 7741..
etc......
year12 = 11604*1.06 = 12338
128 times 2 is 256 divided by 2 is 128 scoops of ice cream
