20e3x = 100
e3x = 5 [Divide both sides by 20]
ln(e3x) = ln(5) [Take the natural log (ln) of both sides]
3x = ln(5)
x = ln(5)/3 ≅ 0.5365
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25x = 24
log2(25x) = log2(24)
5x = log2(23*3) = log2(23) + log2(3)
5x = 3 + log2(3)
x = (3+log2(3))/5 ≅ 0.917