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Finding the Fourth Proportional to 661.78, 993.27 and 457.66

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Solution

The fourth proportional to 661.78, 993.27 and 457.66 is: 686.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.78 : 993.27 = 457.66 : x
  2. Step 2: Convert to fraction form
    661.78/993.27 = 457.66/x
  3. Step 3: Cross multiply
    661.78x = 993.27 × 457.66
  4. Step 4: Simplify right side
    661.78x = 454,579.95
  5. Step 5: Solve for x
    x = 454,579.95/661.78
  6. Step 6: Final answer
    x = 686.90

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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.