I am practicing for a very hard logic competition in Lebanon and I was asked two questions.
Can anyone give me a hint? I really have no idea how to start! I tried to fill in blanks by using the sum, like 0+0.01 = 0.01, then 1.99 + 0.01 = 2 and etc...
I'm stuck.
It's pretty hard to know what's going on from just this, but assuming that the first table is supposed to mean "find two numbers whose sum is given in the right-hand column" and the second table is supposed to mean "find two numbers whose difference is given in the right-hand column" AND the two tables are expecting the same two values for each row (and this is a lot of assumptions...) you have simple simultaneous equations.
The first row becomes: $$ a + b = 230 \quad \mbox{and} \quad a - b = 50 $$ for which the solutions are $a=140$ and $b=90$ (add the two equations to get $2a = 280$, solve for $a$ and substitute back into either equation to solve for $b$).
The last row becomes: $$ a + b = 0.01 \quad \mbox{and} \quad a - b = 0 $$ for which the solutions are $a = 0.005$ and $b=0.005$.
Everything in between you should be able to complete now.
