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Finding the Fourth Proportional to 619.40, 854.43 and 423.20

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Solution

The fourth proportional to 619.40, 854.43 and 423.20 is: 583.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.40 : 854.43 = 423.20 : x
  2. Step 2: Convert to fraction form
    619.40/854.43 = 423.20/x
  3. Step 3: Cross multiply
    619.40x = 854.43 × 423.20
  4. Step 4: Simplify right side
    619.40x = 361,594.78
  5. Step 5: Solve for x
    x = 361,594.78/619.40
  6. Step 6: Final answer
    x = 583.78

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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.