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Finding the Fourth Proportional to 418.95, 628.47 and 145.08

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Solution

The fourth proportional to 418.95, 628.47 and 145.08 is: 217.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.95 : 628.47 = 145.08 : x
  2. Step 2: Convert to fraction form
    418.95/628.47 = 145.08/x
  3. Step 3: Cross multiply
    418.95x = 628.47 × 145.08
  4. Step 4: Simplify right side
    418.95x = 91,178.43
  5. Step 5: Solve for x
    x = 91,178.43/418.95
  6. Step 6: Final answer
    x = 217.64

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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.