"Three days" is the reflexive answer, but let's do the math.
He was taken down from the cross at sundown, IIRC. So that's, let's say, 6 PM, or .25 days.
He wasn't seen from that point through Saturday. Give him all of Saturday, midnight to midnight. That adds up to 1.25 days.
He wasn't in the tomb when the ladies came on Sunday morning. So another .25 days. That's 1.5 days.
He was taken down from the cross at sundown, IIRC. So that's, let's say, 6 PM, or .25 days.
He wasn't seen from that point through Saturday. Give him all of Saturday, midnight to midnight. That adds up to 1.25 days.
He wasn't in the tomb when the ladies came on Sunday morning. So another .25 days. That's 1.5 days.