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Finding the Fourth Proportional to 686.20, 1,029.36 and 253.36

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Solution

The fourth proportional to 686.20, 1,029.36 and 253.36 is: 380.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.20 : 1,029.36 = 253.36 : x
  2. Step 2: Convert to fraction form
    686.20/1,029.36 = 253.36/x
  3. Step 3: Cross multiply
    686.20x = 1,029.36 × 253.36
  4. Step 4: Simplify right side
    686.20x = 260,798.65
  5. Step 5: Solve for x
    x = 260,798.65/686.20
  6. Step 6: Final answer
    x = 380.06

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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.