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Finding the Fourth Proportional to 680.18, 1,018.97 and 419.42

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Solution

The fourth proportional to 680.18, 1,018.97 and 419.42 is: 628.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.18 : 1,018.97 = 419.42 : x
  2. Step 2: Convert to fraction form
    680.18/1,018.97 = 419.42/x
  3. Step 3: Cross multiply
    680.18x = 1,018.97 × 419.42
  4. Step 4: Simplify right side
    680.18x = 427,369.21
  5. Step 5: Solve for x
    x = 427,369.21/680.18
  6. Step 6: Final answer
    x = 628.32

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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.