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Finding the Fourth Proportional to 890.90, 1,229.35 and 517.90

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Solution

The fourth proportional to 890.90, 1,229.35 and 517.90 is: 714.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.90 : 1,229.35 = 517.90 : x
  2. Step 2: Convert to fraction form
    890.90/1,229.35 = 517.90/x
  3. Step 3: Cross multiply
    890.90x = 1,229.35 × 517.90
  4. Step 4: Simplify right side
    890.90x = 636,680.37
  5. Step 5: Solve for x
    x = 636,680.37/890.90
  6. Step 6: Final answer
    x = 714.65

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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.