First what you need to do is make 6meters into centimetres so what how many meters in a centimetre
100cm so you do 100 x 6= 600
After that you do 600 divided by 28 then by 78 then you will find the answer.
Since it is 25% all you would have to do is mutiply it by 4 to get 160. So in conclusion 160 is the answer.
Given:
The base of the given triangle has two part:
Left( left side of the hypotenuse) = 25
Right ( right side of the hypotenuse) = x
The altitude (h) = 60
To find the value of x.
Formula:
By Altitude rule we know that, the altitude of a triangle is mean proportional between the right and left part of the hypotenuse,

Now,
Putting,
left = 25, altitude = 60 and right = x we get,

or,
[ by cross multiplication]
or, 
or, 
Hence,
The value of x is 144.