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Finding the Fourth Proportional to 978.70, 1,470.65 and 540.30

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Solution

The fourth proportional to 978.70, 1,470.65 and 540.30 is: 811.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    978.70 : 1,470.65 = 540.30 : x
  2. Step 2: Convert to fraction form
    978.70/1,470.65 = 540.30/x
  3. Step 3: Cross multiply
    978.70x = 1,470.65 × 540.30
  4. Step 4: Simplify right side
    978.70x = 794,592.20
  5. Step 5: Solve for x
    x = 794,592.20/978.70
  6. Step 6: Final answer
    x = 811.89

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Why These Related Problems?

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