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Finding the Fourth Proportional to 820.62, 1,230.81 and 307.50

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Solution

The fourth proportional to 820.62, 1,230.81 and 307.50 is: 461.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.62 : 1,230.81 = 307.50 : x
  2. Step 2: Convert to fraction form
    820.62/1,230.81 = 307.50/x
  3. Step 3: Cross multiply
    820.62x = 1,230.81 × 307.50
  4. Step 4: Simplify right side
    820.62x = 378,474.08
  5. Step 5: Solve for x
    x = 378,474.08/820.62
  6. Step 6: Final answer
    x = 461.21

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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.