Question

Fond the third proportion of 1.6 and 0.8

Answer 1

Note:
1)The third proportional of two numbers a and b is defined to be that number c such that a : b = b : c.
2) if a:b=c:d then we can write a/b=c/d.

Solution:

So you want to find a number c such that 1.6 : 0.8 = 0.8 : c

​​​​​​We can write,
1.6/0.8 =0.8/c
(See note point one)

So,
​solve the equation to get value of c.

c=(0.8/1.6)×0.8
=0.4

So third proportion of 1.6 and 0.8 is 0.4