A day care worker found 28 children absent one day during an epidemic of chicken pox. If this was 35% of the total number of chi
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Answer:
27.76 grams will be present in 500 years
Step-by-step explanation:
The given formula is , where A is the value of the substance in t years, and
is the initial value
∵ The half-life is a substance is 375 years
- Substitute A by and t by 375 to find the value of k
∴
- Divide both sides by
∴
- Insert ㏑ in both sides
∴ ㏑( ) = ㏑ (
)
- Remember ㏑ ( ) = n
∵ ㏑ ( ) = 375 k
∴ ㏑( ) = 375 k
- Divide both sides by 375
∴ k ≈ -0.00185
∴
∵ 70 grams is present now
- That means the initial value is 70 grams
∴ = 70
∵ The time is 500 years
∴ t = 500
- Substitute the values of and t in the formula
∵
∴ A = 27.76
∴ 27.76 grams will be present in 500 years