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Finding the Fourth Proportional to 652.89, 978.21 and 418.65

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Solution

The fourth proportional to 652.89, 978.21 and 418.65 is: 627.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.89 : 978.21 = 418.65 : x
  2. Step 2: Convert to fraction form
    652.89/978.21 = 418.65/x
  3. Step 3: Cross multiply
    652.89x = 978.21 × 418.65
  4. Step 4: Simplify right side
    652.89x = 409,527.62
  5. Step 5: Solve for x
    x = 409,527.62/652.89
  6. Step 6: Final answer
    x = 627.25

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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.