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Finding the Fourth Proportional to 890.50, 1,228.90 and 517.60

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Solution

The fourth proportional to 890.50, 1,228.90 and 517.60 is: 714.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.50 : 1,228.90 = 517.60 : x
  2. Step 2: Convert to fraction form
    890.50/1,228.90 = 517.60/x
  3. Step 3: Cross multiply
    890.50x = 1,228.90 × 517.60
  4. Step 4: Simplify right side
    890.50x = 636,078.64
  5. Step 5: Solve for x
    x = 636,078.64/890.50
  6. Step 6: Final answer
    x = 714.29

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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.