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Finding the Fourth Proportional to 419.09, 628.80 and 130.55

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Solution

The fourth proportional to 419.09, 628.80 and 130.55 is: 195.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.09 : 628.80 = 130.55 : x
  2. Step 2: Convert to fraction form
    419.09/628.80 = 130.55/x
  3. Step 3: Cross multiply
    419.09x = 628.80 × 130.55
  4. Step 4: Simplify right side
    419.09x = 82,089.84
  5. Step 5: Solve for x
    x = 82,089.84/419.09
  6. Step 6: Final answer
    x = 195.88

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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.