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Finding the Fourth Proportional to 515, 766.64 and 491.40

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Solution

The fourth proportional to 515, 766.64 and 491.40 is: 731.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    515 : 766.64 = 491.40 : x
  2. Step 2: Convert to fraction form
    515/766.64 = 491.40/x
  3. Step 3: Cross multiply
    515x = 766.64 × 491.40
  4. Step 4: Simplify right side
    515x = 376,726.90
  5. Step 5: Solve for x
    x = 376,726.90/515
  6. Step 6: Final answer
    x = 731.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.