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Finding the Fourth Proportional to 809.30, 1,115.60 and 529.50

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Solution

The fourth proportional to 809.30, 1,115.60 and 529.50 is: 729.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    809.30 : 1,115.60 = 529.50 : x
  2. Step 2: Convert to fraction form
    809.30/1,115.60 = 529.50/x
  3. Step 3: Cross multiply
    809.30x = 1,115.60 × 529.50
  4. Step 4: Simplify right side
    809.30x = 590,710.20
  5. Step 5: Solve for x
    x = 590,710.20/809.30
  6. Step 6: Final answer
    x = 729.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.