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Finding the Fourth Proportional to 419.40, 628.68 and 159.36

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Solution

The fourth proportional to 419.40, 628.68 and 159.36 is: 238.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.40 : 628.68 = 159.36 : x
  2. Step 2: Convert to fraction form
    419.40/628.68 = 159.36/x
  3. Step 3: Cross multiply
    419.40x = 628.68 × 159.36
  4. Step 4: Simplify right side
    419.40x = 100,186.44
  5. Step 5: Solve for x
    x = 100,186.44/419.40
  6. Step 6: Final answer
    x = 238.88

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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.