A positive number, when increased by 10, equals 200 times its reciprocal. What is that number?
Correct Answer: Description for Correct answer:
Let the positive number be x
Now, according to question
\( \Large x + 10 = \frac{200}{x} \)
\( \Large x^{2} + 10x = 200 \)
\( \Large x^{2} + 10x - 200=0 \)
\( \Large x^{2} + 20x - 10x - 200 = 0 \)
x(x + 20) - 10(x + 20) = 0
(x - 10)( x + 20) = 0
x = 10 or x = -20
But x is a positive number
\( \Large x \ne -20 \)
\( \Large x = 10 \)
Hence the positive number is 10
option (b)is correct.
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