insert A.M 's between 7 and 71 such that the fifth A.M is 27 Find the number of A.M's

Question

experimentx · Answer

how do you insert AM's in 1,_,_,a ?

anonymous · Answer

(a-1)/ (m+1) = d

anonymous · Answer

1 +d  , 1 + 2d.........

anonymous · Answer

@experimentX  there was a mistake in my question....plzz...read it nw

experimentx · Answer

let there be n AM's between 7 and 71 71 = 7 + nd 27 = 7 + 4d shouldn't be this way ... seems i forgot too. time to google for AM's http://en.wikipedia.org/wiki/Arithmetic_mean

anonymous · Answer

But that Didnt work

anonymous · Answer

27 = 7 + 4d

d = 5

71 = 7 + nd

64 = 5n

n = 64/5,..............

experimentx · Answer

of course this doesn't work because i seem to have forgotten the formula for AM's

anonymous · Answer

A.M   a , b , c

b =  (a + c)/2

experimentx · Answer

i know that ... 
a, _, _, b

experimentx · Answer

a, x, y, b
x = ((a+b)/2 + a)/2
y = (x+b)/2

experimentx · Answer

anonymous · Answer

Foolish.....)...i made a fatal....Mistake...in my calculation...hm.....thxxxxx......))