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Finding the Fourth Proportional to 856.93, 1,286.07 and 309.49

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Solution

The fourth proportional to 856.93, 1,286.07 and 309.49 is: 464.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    856.93 : 1,286.07 = 309.49 : x
  2. Step 2: Convert to fraction form
    856.93/1,286.07 = 309.49/x
  3. Step 3: Cross multiply
    856.93x = 1,286.07 × 309.49
  4. Step 4: Simplify right side
    856.93x = 398,025.80
  5. Step 5: Solve for x
    x = 398,025.80/856.93
  6. Step 6: Final answer
    x = 464.48

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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.