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Finding the Fourth Proportional to 505.84, 758.91 and 418.78

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Solution

The fourth proportional to 505.84, 758.91 and 418.78 is: 628.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.84 : 758.91 = 418.78 : x
  2. Step 2: Convert to fraction form
    505.84/758.91 = 418.78/x
  3. Step 3: Cross multiply
    505.84x = 758.91 × 418.78
  4. Step 4: Simplify right side
    505.84x = 317,816.33
  5. Step 5: Solve for x
    x = 317,816.33/505.84
  6. Step 6: Final answer
    x = 628.29

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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.