It is estimated that 75% of a grapefruit crop is good; the other 25 % have rotten centers that cannot be detected until the grapefruit are cut open. The grapefruit are sold in sacks of 10. We know that the probability of getting no more than 1 bad grapefruit per sack is approximately 0.2440, or 24.40%.

How many sacks should be choosen in order to be sure fewer than 3 bad grapefruit in each sack? Must show work.