How many times did King Jehoash strike the ground with arrows, angering the dying Elisha?

Answer: Three

Jehoash struck only three times. Elisha said five or six strikes would have finished Aram; now he would defeat it only three times.

“Then Elisha said, “Take the arrows!” So he took them, and Elisha said to the king of Israel, “Strike the ground!” So he struck the ground three times and stopped.”— 2 Kings 13:18 (BSB)