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Finding the Fourth Proportional to 856.86, 1,285.83 and 309.30

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Solution

The fourth proportional to 856.86, 1,285.83 and 309.30 is: 464.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.86 : 1,285.83 = 309.30 : x
  2. Step 2: Convert to fraction form
    856.86/1,285.83 = 309.30/x
  3. Step 3: Cross multiply
    856.86x = 1,285.83 × 309.30
  4. Step 4: Simplify right side
    856.86x = 397,707.22
  5. Step 5: Solve for x
    x = 397,707.22/856.86
  6. Step 6: Final answer
    x = 464.14

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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.