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Finding the Fourth Proportional to 642.52, 964.24 and 257.76

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Solution

The fourth proportional to 642.52, 964.24 and 257.76 is: 386.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.52 : 964.24 = 257.76 : x
  2. Step 2: Convert to fraction form
    642.52/964.24 = 257.76/x
  3. Step 3: Cross multiply
    642.52x = 964.24 × 257.76
  4. Step 4: Simplify right side
    642.52x = 248,542.50
  5. Step 5: Solve for x
    x = 248,542.50/642.52
  6. Step 6: Final answer
    x = 386.82

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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.