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Finding the Fourth Proportional to 539.40, 808.35 and 429.90

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Solution

The fourth proportional to 539.40, 808.35 and 429.90 is: 644.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    539.40 : 808.35 = 429.90 : x
  2. Step 2: Convert to fraction form
    539.40/808.35 = 429.90/x
  3. Step 3: Cross multiply
    539.40x = 808.35 × 429.90
  4. Step 4: Simplify right side
    539.40x = 347,509.67
  5. Step 5: Solve for x
    x = 347,509.67/539.40
  6. Step 6: Final answer
    x = 644.25

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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.