1,A ladder with nine rungs is to be built, with the bottom rung 24cm. wide and the top rung

18cm. wide. If the length of the rungs decreases uniformly from bottom to top, how long

should each of the seven intermediate rungs be?

3,Find the first term of the sequence 10, 5, 2.5, 1.25, . . . which is less than 0.0001.

3,In an arithmetic sequence, if the p

th term is q and the q

th term is p, find the (p + q)

th term.
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