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Finding the Fourth Proportional to 653.89, 979.71 and 419.65

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Solution

The fourth proportional to 653.89, 979.71 and 419.65 is: 628.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.89 : 979.71 = 419.65 : x
  2. Step 2: Convert to fraction form
    653.89/979.71 = 419.65/x
  3. Step 3: Cross multiply
    653.89x = 979.71 × 419.65
  4. Step 4: Simplify right side
    653.89x = 411,135.30
  5. Step 5: Solve for x
    x = 411,135.30/653.89
  6. Step 6: Final answer
    x = 628.75

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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.