-4 is also a geometric mean
if we consider a(first element in series)=1 and r(common ratio)=-4 then the series would be
1,-4,16,-64,256,…..,a(-4)^(n-1 )
where n is nth term
from this -4 would be the geometric mean if we consider -4 as common ratio .
If we consider 4 as common ratio then geometric mean should be 4
so you should mention whether common ratio >0 or not (r>0 or not) .
[without ‘r’ value you can’t solve the question but in general most of the teachers will consider r>0.]
So, -4 won’t be geometric mean of 1 & 16
You solve this, you simply divide 32 by 4 to find out how many you can buy. If you divide 32 by 4, you get 8. So you can buy 8 train tickets in total.
Answer:
it should be A
Step-by-step explanation:
When solving these proportions we just remember when moving a number from one side to the other if it started in the numerator it ends up in the denominator and vice versa.
I'll do it in two steps here for teaching purposes; it's not too hard to go directly to the answer.


