https://israelforever.org/state/Mandate_for_Palestine_Jewish_State/
Uh, the 1922 census of the Palestinian Mandate showed ~591,000 Muslims (ostensibly “Palestinians”), ~84,000 Jewish, 73,000 Christian and 7,000 Druse, with a smattering of Hindus, Sikhs and others.
Different sources quote different exact values.
https://users.cecs.anu.edu.au/~bdm/yabber/census/PalestineCensus1922.pdf
https://israelforever.org/state/Mandate_for_Palestine_Jewish_State/
BTW, based on the history I’ve read, the reason there were so few Muslims in the coastal areas is that that is where the Crusaders entered long before and it was considered by most to be a place avoided - just in case.
Of course, the Jews didn’t worry about such stuff when they bought up so much of the land.