Question

Who can solve this......

Answer 1

Let
1st two numbers from left to right be a and b
2nd two numbers from left to right be c and d

We can write the following equations
a + b = 8 …………[1]
c - d = 6 …………[2]
a + c = 13 ………[3]
b + d = 8 ………[4]

Equate 1st and 4th equation
a + b = b + d
a = d

Now, substitute a = d in 2nd equation
c - d = 6
c - a = 6 ………[5]

Add equations [3] and [5]
a + c + c - a = 13 + 6
2c = 19
c = 9.5

If c = 9.5 then from equation [5]
a = c - 6
= 9.5 - 6
= 3.5

Also, we know that a = d
So, d = 3.5

If a = 3.5 then from equation [1]
b = 8 - a
= 8 - 3.5
= 4.5

So, we got
a = 3.5
b = 4.5
c = 9.5
d = 3.5