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Finding the Fourth Proportional to 890.31, 1,228.69 and 517.40

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Solution

The fourth proportional to 890.31, 1,228.69 and 517.40 is: 714.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.31 : 1,228.69 = 517.40 : x
  2. Step 2: Convert to fraction form
    890.31/1,228.69 = 517.40/x
  3. Step 3: Cross multiply
    890.31x = 1,228.69 × 517.40
  4. Step 4: Simplify right side
    890.31x = 635,724.21
  5. Step 5: Solve for x
    x = 635,724.21/890.31
  6. Step 6: Final answer
    x = 714.05

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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.