Respuesta :
Answer:
2/3
Step-by-step explanation:
2 / (1/a + 1/b)
2 / (1/1 + 1/(½))
2 / (1 + 2)
2/3
The harmonic mean is [tex]2\div 3[/tex]
Calculation of the harmonic mean:
Since the string lengths of 1 and 1/2
So,
[tex]= 2 \div (1/a + 1/b)\\\\= 2 \div (1/1 + 1/(1\div 2))\\\\= 2 \div (1 + 2) \\\\= 2\div 3[/tex]
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