This is the 15502nd most frequent Russian word.
предыдущих
"Previous" or "of the previous."
In this sentence, 'предыдущих' is used as a genitive case adjective describing 'уроков', meaning 'previous' as in the lessons that came before the current moment.
Предыдущих уроков оказалось достаточно.
The previous lessons were sufficient.
Here, 'предыдущих' modifies 'встреч' in the genitive plural, indicating meetings that occurred before the current discussion.
Она вспомнила некоторые моменты из предыдущих встреч.
She remembered some moments from the previous meetings.
In this context, 'предыдущих' describes 'экспериментов' in genitive plural, referring to experiments conducted prior to the current one.