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Finding the Fourth Proportional to 347.40, 521.09 and 103.90

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Solution

The fourth proportional to 347.40, 521.09 and 103.90 is: 155.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    347.40 : 521.09 = 103.90 : x
  2. Step 2: Convert to fraction form
    347.40/521.09 = 103.90/x
  3. Step 3: Cross multiply
    347.40x = 521.09 × 103.90
  4. Step 4: Simplify right side
    347.40x = 54,141.25
  5. Step 5: Solve for x
    x = 54,141.25/347.40
  6. Step 6: Final answer
    x = 155.85

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.