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Finding the Fourth Proportional to 419.19, 628.80 and 130.69

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Solution

The fourth proportional to 419.19, 628.80 and 130.69 is: 196.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.19 : 628.80 = 130.69 : x
  2. Step 2: Convert to fraction form
    419.19/628.80 = 130.69/x
  3. Step 3: Cross multiply
    419.19x = 628.80 × 130.69
  4. Step 4: Simplify right side
    419.19x = 82,177.87
  5. Step 5: Solve for x
    x = 82,177.87/419.19
  6. Step 6: Final answer
    x = 196.04

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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.