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Finding the Fourth Proportional to 612.89, 919.47 and 287.87

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Solution

The fourth proportional to 612.89, 919.47 and 287.87 is: 431.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.89 : 919.47 = 287.87 : x
  2. Step 2: Convert to fraction form
    612.89/919.47 = 287.87/x
  3. Step 3: Cross multiply
    612.89x = 919.47 × 287.87
  4. Step 4: Simplify right side
    612.89x = 264,687.83
  5. Step 5: Solve for x
    x = 264,687.83/612.89
  6. Step 6: Final answer
    x = 431.87

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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.