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Finding the Fourth Proportional to 686.72, 948.72 and 511.76

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Solution

The fourth proportional to 686.72, 948.72 and 511.76 is: 707.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.72 : 948.72 = 511.76 : x
  2. Step 2: Convert to fraction form
    686.72/948.72 = 511.76/x
  3. Step 3: Cross multiply
    686.72x = 948.72 × 511.76
  4. Step 4: Simplify right side
    686.72x = 485,516.95
  5. Step 5: Solve for x
    x = 485,516.95/686.72
  6. Step 6: Final answer
    x = 707.01

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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.