Birkat haMazon or Minchah?

Hi,

We are taught that one may recite the birkat hamazon blessing after meals only up to 72 minutes after the conclusion of a meal. What if the latest time to recite minchah is arriving, but by the end of minchah the 72 minutes would elapse and he would lose the chance to recite birkat hamazon?

Ideally, one should eat a little more and so extend the 72 minutes. Where that is not possible, one should recite birkat hamazon. First, birkat hamazon is a biblical obligation [if the meal was to the point of satiation - MT]. Second, one who is unable to recite minchah due to circumstances beyond his control is then allowed to recite maariv twice, as a make-up.

(Rivivot Ephraim 1:162)

Have a great day,
Mordechai