Question about direction of heat

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To determine the final temperature when two objects with different masses and specific heats are placed in water, it's essential to identify the direction of heat transfer. The heat loss must be calculated based on which object loses energy, as this affects the percentage of heat loss applied. The equation q1 + q2 + q3 = q_loss is used, where q_loss depends on the negative values of q1, q2, or q3, indicating energy loss. Understanding that heat flows from hotter to colder objects is crucial for establishing the direction of heat transfer. A definitive method to ascertain the direction without knowing the final temperature remains elusive.
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If 2 object with different masses and different specific heat at different Temperature are put in water that have certain mass and temperature. If the heat loss is count by percent (that is, let's say 20% of heat is lost). Find the final temperature

To solve this problem, I have to first determine the direction of the heat; that is, if i don't know which system gains energy and which system lose energy, then i will not know which q do i have to apply the 20% heat loss to.

So

q1 + q2 + q3 = q_loss

where q_loss can either be:
0.2(q1) --> if q1 is negative (object1 lose energy)
0.2(q2) --> if q2 is negative ,,
0.2(q3) --> if q3 is negative ,,
0.2(q1+q2) --> if q1 and q2 are negative
0.2(q2+q3) --> if q2 and q3 are negative
0.2(q1+q3) --> if q1 and q3 are negative

To find q_loss, we need to know which one is negative; we need to know the change in temperature (however, final temp is unknown). Therefore, is there another method to determine the direction of heat for each individual object without having to do trial and error method?

I think there must be a way to know the direction without knowing the final temperature. However, my attempt has failed
 
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