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Finding the Fourth Proportional to 807, 1,207.35 and 688.38

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Solution

The fourth proportional to 807, 1,207.35 and 688.38 is: 1,029.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    807 : 1,207.35 = 688.38 : x
  2. Step 2: Convert to fraction form
    807/1,207.35 = 688.38/x
  3. Step 3: Cross multiply
    807x = 1,207.35 × 688.38
  4. Step 4: Simplify right side
    807x = 831,115.59
  5. Step 5: Solve for x
    x = 831,115.59/807
  6. Step 6: Final answer
    x = 1,029.88

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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.