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Finding the Fourth Proportional to 978.81, 1,469.84 and 805.47

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Solution

The fourth proportional to 978.81, 1,469.84 and 805.47 is: 1,209.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    978.81 : 1,469.84 = 805.47 : x
  2. Step 2: Convert to fraction form
    978.81/1,469.84 = 805.47/x
  3. Step 3: Cross multiply
    978.81x = 1,469.84 × 805.47
  4. Step 4: Simplify right side
    978.81x = 1,183,908.00
  5. Step 5: Solve for x
    x = 1,183,908.00/978.81
  6. Step 6: Final answer
    x = 1,209.54

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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.