Data Sufficiency (DS) | Three apples of distinct weights, are weighed two at a time, such that

Three apples of distinct weights, are weighed two at a time, such that all three possible pairs are weighed exactly once. The three weights of three distinct pairs of apples thus recorded are X, Y and Z grams respectively, such that X < Y < Z. What is the weight of the lightest apple among the three ?

(1) X + Y + Z = 420 grams

(2) Z = 145 grams

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