7 days (that took just one minute to answer)
'Third Quarter' occurs 7.38 days after a Full Moon.After the Third Quarter, you'd have to wait 22.1 daysfor the next Full Moon.
The time period between Full Moon and Third Quarter is usually 7 or 8 days, depending on the actual Full Moon and Third Quarter times.
its called waning gibbous
During it's normal course of phases, from full moon to last quarter is about a week.
Waxing gibbous
About 7
It takes approximately 7.4 days from a full moon to reach the third quarter phase.
The phase that occurs between the first quarter moon and the full moon is the waxing gibbous phase. During this phase, the illuminated portion of the moon continues to grow larger each night until it reaches full illumination.
Waxing Gibbous
The waning gibbous moon does.
1st quarter moon . . . 7.38 days after New Moon Full moon . . . 14.77 days after New Moon 3rd quarter moon . . . 22.15 days after New Moon New Moon . . . 29.53 days after the previous New Moon.
I believe that the anwser is last quarter.