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Finding the Fourth Proportional to 820.55, 1,228.86 and 454.43

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Solution

The fourth proportional to 820.55, 1,228.86 and 454.43 is: 680.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.55 : 1,228.86 = 454.43 : x
  2. Step 2: Convert to fraction form
    820.55/1,228.86 = 454.43/x
  3. Step 3: Cross multiply
    820.55x = 1,228.86 × 454.43
  4. Step 4: Simplify right side
    820.55x = 558,424.71
  5. Step 5: Solve for x
    x = 558,424.71/820.55
  6. Step 6: Final answer
    x = 680.55

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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.