1 hour equals 70 miles so 70 times 4 equals 280 and half of 70 is 35 since you traveled 4.5 hours and 280+35 equals 315
Your interest formula is given to you.
Interest in a year = principal (the amount invested) * rate (the interest rate) * period (the time you're measuring)
Interest = 55,000 * 2% * 1 year = 55,000 * 0.02 * 1 = $1,100
How much would you need to have made for your spending power to keep with inflation? Your interest rate would have needed to match the inflation rate, otherwise prices are going up faster than you're saving.
Required interest = 55,000 * 3.24% * 1 year = 55,000 * 0.0324 * 1 = $1,782
How much buying power did you lose? The difference between your required interest and your actual interest.
Buying power lost = 1,782 - 1,100 = $682. You lost this much in buying power.
Hope that helped :)
Identity property of addition
