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Finding the Fourth Proportional to 430.40, 644.99 and 247.85

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Solution

The fourth proportional to 430.40, 644.99 and 247.85 is: 371.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.40 : 644.99 = 247.85 : x
  2. Step 2: Convert to fraction form
    430.40/644.99 = 247.85/x
  3. Step 3: Cross multiply
    430.40x = 644.99 × 247.85
  4. Step 4: Simplify right side
    430.40x = 159,856.31
  5. Step 5: Solve for x
    x = 159,856.31/430.40
  6. Step 6: Final answer
    x = 371.42

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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.