# What are the missing numbers in this group of 7?

The following groups of 7 number in each line, are related in each line in a unique way:

1   3   1.5 12.25   1   2   3

1.5 6   2   42.25   1   3   4

3   6   4   61      2   3   4


What are the numbers to replace the "?" in following list?

1   5   2.5 32.25   ?   ?   ?


Hint: An object

The missing numbers are:

1 2 5

Because:

Lets say numbers are marked in order like:
x y z n a b c
You can find that:
x = a*b/2
y = b*c/2
z = a*c/2

1 5 2.5 32.25 ? ? ?
1 = a*b/2
5 = b*c/2
2.5 = a*c/2
->
2 = a*b
10 = b*c
5 = a*c
->
a = 5/c = 2/b
a*b*c = 5b = 2c
->
10a = 5b = 2c ->
10 * 1 = 5 * 2 = 2 * 5
So missing numbers are:
1 2 5
But I don't know what middle number n should represent.

• Nice. Pretty sure your n is rot(gur fhz bs k^2, l^2 naq m^2). You could then derive a relationship to your a, b and c as well if it helps to confirm your answer... – Stiv Sep 10 '19 at 13:13
• Stiv provided an insight (what is this rot(gur fhz bs k^2, l^2 naq m^2)?:)). – Moti Sep 10 '19 at 23:10
• This is the relation of the faces of right angle pyramid – Moti Sep 10 '19 at 23:11