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Finding the Fourth Proportional to 429.95, 645.79 and 256.96

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Solution

The fourth proportional to 429.95, 645.79 and 256.96 is: 385.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.95 : 645.79 = 256.96 : x
  2. Step 2: Convert to fraction form
    429.95/645.79 = 256.96/x
  3. Step 3: Cross multiply
    429.95x = 645.79 × 256.96
  4. Step 4: Simplify right side
    429.95x = 165,937.68
  5. Step 5: Solve for x
    x = 165,937.68/429.95
  6. Step 6: Final answer
    x = 385.95

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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.