How do I find t
4.0=5.0e^(-t/14960)
Show working
2007-12-16 21:46:41 · 5 answers · asked by Selly 3 in Science & Mathematics ➔ Mathematics
4/5 = e^(-t/14960)
ln(0.8) = -t/14960
t = -14960*ln(0.8) = 3338.23
i believe this has something to do with half-life...
§
2007-12-16 21:51:45 · answer #1 · answered by Alam Ko Iyan 7 · 1⤊ 1⤋
4 = 5 e^(-t/14960)
4/5 = e ^(-t/14960)
ln (4/5) = ln e ^(-t/14960)
ln (4/5) = -t/14960
ln (4/5) * 14960 = -t
ln (4/5) * -14960 = t
I don't have a calculator with me, but you can punch in LN of 4/5 and multiply it by -14960 to get t.
2007-12-16 21:53:06 · answer #2 · answered by Romeo 3 · 1⤊ 1⤋
4 = 5 e^(- t / 14960)
4 / 5 = e^(- t / 14960)
ln (4/5) = - t / 14960
t = - (14960) ln (4/5)
t = 3,338 to nearest whole number.
2007-12-16 22:00:56 · answer #3 · answered by Como 7 · 4⤊ 1⤋
4.0=5.0e^(-t/14960), you start by taking in of both sides
ln 4.0 = ln 5.0 + ln e^(-t/14960)
ln 4.0 = ln 5.0 + (-t/14960) ln e
1.386 = 1.609 +(-t/14960)
t/14960 = 1.609 - 1.386
t/14960 = 0.223
t = 0.233 * 14960
t = 33360.08
2007-12-16 21:59:18 · answer #4 · answered by Anonymous · 1⤊ 1⤋
4 = 5e^(-t/14960) may be written as
4 = 5/(e^(t/14960))
Transposing
4e^(t/14960) = 5
e^(t/14960) = 5/4
Taking the ln of both sides of the equation
ln (e^(t/14960) = ln(5/4)
Thus,
t/14960 = ln(5/4)
t=14960*ln(5/4)
t= 14960*0.223
t=3338
2007-12-16 22:00:34 · answer #5 · answered by Romy C 5 · 1⤊ 1⤋