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Finding the Fourth Proportional to 418.90, 628.37 and 145.02

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Solution

The fourth proportional to 418.90, 628.37 and 145.02 is: 217.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.90 : 628.37 = 145.02 : x
  2. Step 2: Convert to fraction form
    418.90/628.37 = 145.02/x
  3. Step 3: Cross multiply
    418.90x = 628.37 × 145.02
  4. Step 4: Simplify right side
    418.90x = 91,126.22
  5. Step 5: Solve for x
    x = 91,126.22/418.90
  6. Step 6: Final answer
    x = 217.54

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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.