Ten cubits was the length of a board, and a cubit and a half the breadth of each board.
King James Version (KJV) - Exodus 36:21 >The length of a board [was] ten cubits, and the breadth of a board one cubit and a half.
Berean Study Bible (BSB) - Exodus 36:21 >Each frame was ten cubits long and a cubit and a half wide.