Exodus 7:25
Seven days passed after the Lord had struck the Nile.
Exodus 8:9-10
And Moses said to Pharaoh, “I am entirely at your service: when shall I plead [with the Lord] for you and your servants and your people, so that the frogs may leave you and your houses and remain only in the Nile?”
Exodus 10:23
The Egyptians could not see one another, nor did anyone leave his place for three days, but all the Israelites had [supernatural] light in their dwellings.
2 Samuel 24:13
So Gad came to David and told him, and said to him, “Shall seven years of famine come to you in your land? Or will you flee three months before your enemies as they pursue you? Or shall there be three days of pestilence (plague) in your land? Now consider this and decide what answer I shall return to Him who sent me.”