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Finding the Fourth Proportional to 856.82, 1,285.80 and 309.04

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Solution

The fourth proportional to 856.82, 1,285.80 and 309.04 is: 463.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.82 : 1,285.80 = 309.04 : x
  2. Step 2: Convert to fraction form
    856.82/1,285.80 = 309.04/x
  3. Step 3: Cross multiply
    856.82x = 1,285.80 × 309.04
  4. Step 4: Simplify right side
    856.82x = 397,363.63
  5. Step 5: Solve for x
    x = 397,363.63/856.82
  6. Step 6: Final answer
    x = 463.77

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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.