Answer 1

The given pair of equation are: 
`x/2 + y = 0.8             =>x + 2y = 1.6...(a)`      
`7/(x + y/2) = 10        =>7 = 10(x + y/2)        => 7 = 10x + 5y`

Lets multiply LHS and RHS of equation (a) by 10 for easy calculation
So, we finally get
10x + 20y = 16 .................(i) And,
10x + 5y = 7.................(ii)

Now, Subtracting two equations we get,
`=>` (i) - (ii)
15y = 9
`=> y = 3/5`

Next, putting the value of y in the equation (i) we get,
x = `[16 - 20(3/5)]/10`

`=> (16 - 12)/10 = 4/10`

`x = 2/5`
Thus, the value of x and y obtained are `2/5` and `3/5` respectively.