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Finding the Fourth Proportional to 686.40, 1,029.60 and 301.65

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Solution

The fourth proportional to 686.40, 1,029.60 and 301.65 is: 452.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.40 : 1,029.60 = 301.65 : x
  2. Step 2: Convert to fraction form
    686.40/1,029.60 = 301.65/x
  3. Step 3: Cross multiply
    686.40x = 1,029.60 × 301.65
  4. Step 4: Simplify right side
    686.40x = 310,578.84
  5. Step 5: Solve for x
    x = 310,578.84/686.40
  6. Step 6: Final answer
    x = 452.48

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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.