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Finding the Fourth Proportional to 686.45, 1,028.75 and 571.62

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Solution

The fourth proportional to 686.45, 1,028.75 and 571.62 is: 856.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.45 : 1,028.75 = 571.62 : x
  2. Step 2: Convert to fraction form
    686.45/1,028.75 = 571.62/x
  3. Step 3: Cross multiply
    686.45x = 1,028.75 × 571.62
  4. Step 4: Simplify right side
    686.45x = 588,051.22
  5. Step 5: Solve for x
    x = 588,051.22/686.45
  6. Step 6: Final answer
    x = 856.66

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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.