Final answer:
The question implicates a mathematical problem of combinatorics involving weighing combinations of diamonds in pairs, likely requiring knowledge of combinations and algebra to solve.
Step-by-step explanation:
The question 'When 3 large diamonds are weighed in pairs' suggests a problem that involves combinatorics and possibly measurement in mathematics. The act of weighing diamonds in pairs would typically require the application of combinations, where the 3 diamonds can form 3 distinct pairs to be weighed: Diamond 1 with Diamond 2, Diamond 1 with Diamond 3, and Diamond 2 with Diamond 3. This is an example of combination without repetition, denoted in mathematical terms as C(n, k) where n is the total number of items and k is the number of items to choose, which in this case would be C(3, 2).
Apart from combinatorics, if the question involved calculating the individual weights of the diamonds based on the pair weights, algebra might be used to set up equations and solve for the unknown weights of the individual diamonds. In the absence of further context, it is not possible to give a specific mathematical solution.