To calculate the total percent markdown when using the three discounts in series, we can multiply the discounts and subtract the result from 100%.
Starting with the largest discount of 55%, we can multiply the discounts in series as follows:
55% x 35% x 15% = 2.29625%
So, the total percent markdown when using the discounts in series would be approximately 2.3%, rounded to the nearest whole percent.
Therefore, using the discounts in series would result in a total markdown of about 2%.