What is the necessary duration of fasting as expiation for repeated breaking of an oath (9 times for abandoning a sin, twice for waking up for Fajr prayer, and once for abandoning a sin for 10 days) for someone who is only able to fast?

If a person swears twelve oaths and breaks each one, then he owes twelve expiations. If he is unable to feed, clothe, or free a slave, then he must fast three days for each oath. It is more cautious to fast the three days consecutively for each expiation. The total number of days he must fast would be thirty-six days. However, if the oaths were taken concerning one single matter before the breaking of the oath, then only one expiation is required.