text: ## Question
  
  Secondary 1 | Maths
  
  Anyone can contribute an answer, even non-tutors.
  
  ##### Megan
  
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  It would be great if you could solve and explain the question to me.
  
  Date Posted: 1 year ago
  Views: 124
  Eric Nicholas K
  1 year ago
  Replacing a by 1/2,
  1/a = 1 divided by a = 1 divided by 1/2 = 1 x 2 = 2.
  
  Replacing b by 1/4,
  1/b = 1 divided by b = 1 divided by 1/4 = 1 x 4 = 4.
  
  Replacing d by -1/5,
  1/d = 1 divided by d = 1 divided by (-1/5) = 1 x (-5) = -5.
  
  Now, 1/a - 1/b = 1/c + 1/d.
  
  But 1/a = 2, 1/b = 4 and 1/d = -5.
  
  So, 2 - 4 = 1/c - 5
  1/c = 2 - 4 + 5 = 3
  1/c = 3
  1 = 3c
  c = 1/3