arithmetic math question!?

Question

find three arithmetic means between -2 and 12

i dont get that...

Answer 1

I don't get it either. Is this the whole problem?

1, 2, 3, Mean is 2
7, 7, 7, Mean is 7
-1, 3, 10, Mean is 4

Answer 2

for three arithmetic means between --2 and 12, the common difference is given by
x = (b -- a)/(n + 1) where in this question
a = --2,
b = 12,
n = 3 whence
x = (12 + 2)/(3 +1)
x = 7/2 giving
first mean A1 = a + x = --2 + 7/2 = 3/2
second A2 = A1 + x = 3/2 + 7/2 = 5
third A3 = A2 + x = 5 + 7/2 = 17/2
The required means are 3/2, 5, 17/2

Answer 3

if arthimetic means between a and b =3
so total terms = 5
first term = a
last term = b
last term = a + (n -1)d,
where a = first term
n= total terms
d = common difference
in the given problem first term = -2
last term =12
total terms =5
so 12 = -2 + (5 - 1)d
12 = -2 + 4d
4d = 12 + 2 = 14
d = 14/4 = 7/2
So first term = -2
second term = -2 + 7/2 = 3/2
third term = 3/2 + 7/2 = 5
fourth term = 5 + 7/2 = 17/2
last term = 17/2 + 7/2 = 12
So three arithmetic means = (3/2), 5, (17/2)

Answer 4

12+2 = 14
14/4 = 7/2 = 3.5
1.5, 5, 8.5, the three arithmetic means between -2 and 12

Answer 5

The arithmetic mean is (-2+12)/2 = 5
The geometric mean is sqrt(-24) = 2isqrt(6) and is imaginary
The harmonic mean is 2/(1/-2 +1/12) which is -24/5 which is meaningless.
Are you sure you have quoted the problem correctly?

Answer 6

12 = -2 + 4d
d = 14/4 = 7/2
progression : -2 , 3/2 , 5 , 17/2 , 12