The weight of substance remaining after 13 years is 2.25 g.
Given:
Present weight of substance = 12 g
After 8 years weight remains = 6 gm
Now, weight loss in 8 year will be,
12-6=6 gm
So, weight loss in 1 year will be,
Total weight loss in 13 year will be,
The weight of substance remaining after 13 years will be,
Therefore, the weight of substance remaining after 13 years is 2.25 g.
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