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Finding the Fourth Proportional to 856.41, 1,285.61 and 685.17

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Solution

The fourth proportional to 856.41, 1,285.61 and 685.17 is: 1,028.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.41 : 1,285.61 = 685.17 : x
  2. Step 2: Convert to fraction form
    856.41/1,285.61 = 685.17/x
  3. Step 3: Cross multiply
    856.41x = 1,285.61 × 685.17
  4. Step 4: Simplify right side
    856.41x = 880,857.98
  5. Step 5: Solve for x
    x = 880,857.98/856.41
  6. Step 6: Final answer
    x = 1,028.55

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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.