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Finding the Fourth Proportional to 647.78, 971.46 and 257.88

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Solution

The fourth proportional to 647.78, 971.46 and 257.88 is: 386.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.78 : 971.46 = 257.88 : x
  2. Step 2: Convert to fraction form
    647.78/971.46 = 257.88/x
  3. Step 3: Cross multiply
    647.78x = 971.46 × 257.88
  4. Step 4: Simplify right side
    647.78x = 250,520.10
  5. Step 5: Solve for x
    x = 250,520.10/647.78
  6. Step 6: Final answer
    x = 386.73

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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.