Acoin is tossed, them a number 1-10 is chosen at random. what is the probability of getting heads then a number less then 4

Keisha makes a large sandwich for a family picnic she takes 1/2 of them the sandwich to the picnic her family eats 3/8 of the whole sandwich what fraction of the whole sandwich does keisha bring back from the picnic

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In triangle △abc, ∠abc=90°, bh is an altitude. find the missing lengths. ah=4 and hc=1, find bh.