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Finding the Fourth Proportional to 856.88, 1,285.49 and 343.88

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Solution

The fourth proportional to 856.88, 1,285.49 and 343.88 is: 515.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.88 : 1,285.49 = 343.88 : x
  2. Step 2: Convert to fraction form
    856.88/1,285.49 = 343.88/x
  3. Step 3: Cross multiply
    856.88x = 1,285.49 × 343.88
  4. Step 4: Simplify right side
    856.88x = 442,054.30
  5. Step 5: Solve for x
    x = 442,054.30/856.88
  6. Step 6: Final answer
    x = 515.89

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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.