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Answer:
- 1.568
Step-by-step explanation:
Let's assume that the base of the given logarithm is 10.
log m = 0.345 ⇒ [tex]10^{0.345}[/tex] = m
log n = 1.223 ⇒ [tex]10^{1.223}[/tex] = n
mn = [tex]10^{0.345}[/tex] × [tex]10^{1.223}[/tex] = [tex]10^{1.568}[/tex]
[tex]\frac{1}{mn}[/tex] = [tex]10^{-1.568}[/tex]
log [tex]10^{-1.568}[/tex] = - 1.568 × log 10 = - 1.568