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Finding the Fourth Proportional to 820.28, 1,230.34 and 307.32

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Solution

The fourth proportional to 820.28, 1,230.34 and 307.32 is: 460.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.28 : 1,230.34 = 307.32 : x
  2. Step 2: Convert to fraction form
    820.28/1,230.34 = 307.32/x
  3. Step 3: Cross multiply
    820.28x = 1,230.34 × 307.32
  4. Step 4: Simplify right side
    820.28x = 378,108.09
  5. Step 5: Solve for x
    x = 378,108.09/820.28
  6. Step 6: Final answer
    x = 460.95

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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.