The sum of the reciprocal of a number and 2/5 is 1/2. Find the number

Question

Test.                         

Answer 1

(1/n) + (2/5) = 1/2

(1/n) = (1/2) - (2/5)

(1/n) = (5/10) - (4/10) = 1/10

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Ans: n = 10

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Check:  (1/10) + (2/5) = (1/10) + (4/10) = 5/10 = 1/2  (ok)