Question

If `x/4  + y/3 = 15/12  and x/2 + y = 1,` then find the value of (x + y).

Answer 1

The given pair of equations is
  `x/4 + y/3 = 5/12 `            ………(i)
`x/2 + y = 1`                       ………(ii)
Multiplying (i) by 12 and (ii) by 4, we have
3x + 4y = 5                            ……….(iii)
2x + 4y = 4                            ………(iv)
Now, subtracting (iv) from (iii), we get
x = 1
Putting x = 1 in (iv), we have
2 + 4y =4
⇒ 4y = 2
⇒ y =`1/2`
∴ x + y = 1 + `1/2 = 3/2 `
Hence, the value of x + y is `3/2`