no number can have a positive and a negative at the same time. a negative number has a negative sign and a positive number has a plus sign.
2/4 is one you could put because 2/4 = 1/2 = 6/12, and 6/12 is less than 7/12.
Glad I could help, and good luck!
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Answer: 4 years
Step-by-step explanation:
A(0) has to be amount at start. Assume that's 5mg
Then A(t) = 5×(0.5)^(0.25t) = 5×2^(-t/4),
(also known as 5 exp(-λ t) with λ = ln(2)/4, incidentally).
We need to such that A(t) = 2.5mg, or 2^(-t/4) is 1/2, which happens when -t/4 is -1, or t is 4.
If it's adding to the 4,900 in the bank just add the numbers to 4,900.
After 4 years. 1,176.
Year 1: 294
Year 2: 588
Year 3: 882
Year 4: 1176
Year 5: 1470
Year 6: 1764
