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Finding the Fourth Proportional to 857.83, 1,284.57 and 686.47

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Solution

The fourth proportional to 857.83, 1,284.57 and 686.47 is: 1,027.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    857.83 : 1,284.57 = 686.47 : x
  2. Step 2: Convert to fraction form
    857.83/1,284.57 = 686.47/x
  3. Step 3: Cross multiply
    857.83x = 1,284.57 × 686.47
  4. Step 4: Simplify right side
    857.83x = 881,818.77
  5. Step 5: Solve for x
    x = 881,818.77/857.83
  6. Step 6: Final answer
    x = 1,027.96

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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.