@sadiafatma1278 11 if looking at one side only. 18 if taking into account holes on both sides of the jumper. ie. each hole is 2 holes (one on each side of the jumper), plus one hole for the collar, one for the bottom of the jumper, and one for each sleeve.
@elonmuskPBG Well the answer is 2 ie. The couple. There is nothing in that text to suggest anyone else attended the picnic. It’s surprising then that 90% of those from MIT who attempted it got it wrong.