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Finding the Fourth Proportional to 480.28, 720.42 and 138.28

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Solution

The fourth proportional to 480.28, 720.42 and 138.28 is: 207.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    480.28 : 720.42 = 138.28 : x
  2. Step 2: Convert to fraction form
    480.28/720.42 = 138.28/x
  3. Step 3: Cross multiply
    480.28x = 720.42 × 138.28
  4. Step 4: Simplify right side
    480.28x = 99,619.68
  5. Step 5: Solve for x
    x = 99,619.68/480.28
  6. Step 6: Final answer
    x = 207.42

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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.