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Finding the Fourth Proportional to 708.80, 978 and 428.96

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Solution

The fourth proportional to 708.80, 978 and 428.96 is: 591.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    708.80 : 978 = 428.96 : x
  2. Step 2: Convert to fraction form
    708.80/978 = 428.96/x
  3. Step 3: Cross multiply
    708.80x = 978 × 428.96
  4. Step 4: Simplify right side
    708.80x = 419,522.88
  5. Step 5: Solve for x
    x = 419,522.88/708.80
  6. Step 6: Final answer
    x = 591.88

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