Whats the missing term in the geometric sequence 36, __, 4?

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Answer 1 · 2015-11-27T10:39:38

#x = 12#

Now let the Middle term be #x#

#36, x, 4#

So the definition of a geometric series is

#a, ar,ar^2 ....ar^(n-1#
|_____|

    n terms

Now from this we can come to some results

#1) ->36*r = x#

This is because every step of the series is being multiplied by a common number #r#

#2)-> x*r = 4#

Now from #ox1#

#=>36 *r*r = 4#

#=>cancel 4 *9 *r^2 = cancel4#

#=> r^2 = 1/9, r = 1/3#

#36*1/3 = x#

#cancel3 * 12*1/cancel3 = x#

#therefore x = 12#