The answer is x=-4, (3<span>±i)/2</span>
the weight of the substance after 28 years is 8 grams.
<h3>How to determine the amount</h3>
We have that the half life of a substance is defined as the time required for the substance to decrease by half
The formula for calculating the half - life of a material is given as;

Where
- N(t) is final amount
- No is the initial amount = 128 grams
- t1/2 is the half life = 7 years
- t is the time elapsed = 28 years
Substitute into the formula
N(t) = 128 × (0. 5) ^28/ 7
N (t) = 128 × ( 0. 5) ^ 4
N(t) = 128 × 0. 0625
N(t) = 8 grams
Thus, the weight of the substance after 28 years is 8 grams.
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Answer:
21900
Step-by-step explanation:
Find 8% of 7500 (600) and multiply it by 24 (amount of months) then add that to 7500
256 is the answer to this question.
800x.32 equals 256 seventh graders
Answer: f(x)=567(1/3)^x
Step-by-step explanation:
At x = 0 y = 567
at x = 1 y = 567 - 567(1/3)
at x = 2 y = 567 - 567(1/3)(1/3)
at x = 3 y = 567 - 567(1/3)(1/3)(1/3