"His anger shall send against them burning hot, fury, and indignation, and distress, a company of destroying angels." Rabbi Yosei the Galilean says, "Ten plagues were inflicted upon the Egyptians in Egypt, as it is said (Exodus 8:15), 'It is the finger of God.' How many plagues are there in one finger? Ten plagues.
Henceforth, it should be said that at the sea, fifty plagues were inflicted upon them, as it is said (Exodus 14:31), 'And Israel saw the great hand.' A hand has five fingers." Rabbi Eliezer says, "There were forty plagues, as it is said (Exodus 8:15), 'It is the finger of God.' Tetragon was there, and there were forty plagues in Egypt.
And at the sea, two hundred plagues were inflicted upon them, as it is said (Exodus 15:8), 'His anger sent against them burning hot, fury, and indignation, and distress, a company of destroying angels.' One distress, two angers, three afflictions, and four companies of destroying angels. Hence, there were two hundred plagues that were inflicted upon them at the sea, as it is said (Exodus 14:31), 'And Israel saw the great hand which the Lord had used against the Egyptians.'
Rabbi Akiva says, 'Fifty plagues were inflicted upon each and every Egyptian in Egypt, as it is said (Psalms 82:1), 'God stands in the congregation of God.' It is a Pentagon (edit. פֶּנְטִיגוֹן, פִּינְ׳, פּוּנְ׳ m. 1) (πεντάγωνος) pentagonal. Naz. 8ᵇ; B. Bath. 164ᵇ פ׳ (בית) a pentagonal building; Tosef. Neg.
VI, 3 פנטיגין ed. Zuck. (oth. ed. פנטניז, corr. acc.). —2) (πεντάγονος) for the fifth time. Naz. l. c.; B. Bath. l. c., v. דִּיגוֹן. —3) fivefold. Midr.
Till. to Ps. LXXVIII, 49 פ׳ היה (not היא; ed. Bub. טטראגון הוא, corr. acc.) each Egyptian plague was fivefold. [M. Jastrow]), and it is said (Exodus 8:15), 'It is the finger of God.' And the tops of the fingers are ten, hence there were fifty plagues. And at the sea, there were two hundred and fifty plagues inflicted upon them, as it is said (Exodus 15:8), 'His anger shall send against them burning hot, fury, and indignation, and distress, a company of destroying angels.' One burning hot, two distresses, three angers, four afflictions, and five companies of destroying angels."