Lemma
MediumExponentials & logarithms
#1625 · Algebra · Exponentials & logarithms

Discount as harmonic mean

Shew that at simple interest the discount is half the harmonic mean between the sum due and the interest on it.

~10 minProof · checked by AIsimple interestharmonic meandiscount

H. S. Hall & S. R. Knight, Higher Algebra (1891) · Ch. XVIII. Interest and Annuities, Examples XVIII.a, No. 6

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