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Finding the Fourth Proportional to 928.20, 1,280.85 and 508.47

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Solution

The fourth proportional to 928.20, 1,280.85 and 508.47 is: 701.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    928.20 : 1,280.85 = 508.47 : x
  2. Step 2: Convert to fraction form
    928.20/1,280.85 = 508.47/x
  3. Step 3: Cross multiply
    928.20x = 1,280.85 × 508.47
  4. Step 4: Simplify right side
    928.20x = 651,273.80
  5. Step 5: Solve for x
    x = 651,273.80/928.20
  6. Step 6: Final answer
    x = 701.65

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.