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Finding the Fourth Proportional to 928.85, 1,281.78 and 509.18

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Solution

The fourth proportional to 928.85, 1,281.78 and 509.18 is: 702.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    928.85 : 1,281.78 = 509.18 : x
  2. Step 2: Convert to fraction form
    928.85/1,281.78 = 509.18/x
  3. Step 3: Cross multiply
    928.85x = 1,281.78 × 509.18
  4. Step 4: Simplify right side
    928.85x = 652,650.33
  5. Step 5: Solve for x
    x = 652,650.33/928.85
  6. Step 6: Final answer
    x = 702.65

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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.