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Finding the Fourth Proportional to 686.51, 946.96 and 499.47

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Solution

The fourth proportional to 686.51, 946.96 and 499.47 is: 688.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.51 : 946.96 = 499.47 : x
  2. Step 2: Convert to fraction form
    686.51/946.96 = 499.47/x
  3. Step 3: Cross multiply
    686.51x = 946.96 × 499.47
  4. Step 4: Simplify right side
    686.51x = 472,975.61
  5. Step 5: Solve for x
    x = 472,975.61/686.51
  6. Step 6: Final answer
    x = 688.96

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.