80% of a number is x
so let us say the number is y
that means 80 % of y is x.
Making an equation we have,

So solving for y we have,

Now we have to find what is 40 % of the number.
So we have to find 40 % of y here
0.04 *y = 0.04 (12.5 x)
y=1.5 x
So we can say that 40 % of the number is 1.5 x