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Finding the Fourth Proportional to 320.63, 480.87 and 138.11

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Solution

The fourth proportional to 320.63, 480.87 and 138.11 is: 207.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.63 : 480.87 = 138.11 : x
  2. Step 2: Convert to fraction form
    320.63/480.87 = 138.11/x
  3. Step 3: Cross multiply
    320.63x = 480.87 × 138.11
  4. Step 4: Simplify right side
    320.63x = 66,410.55
  5. Step 5: Solve for x
    x = 66,410.55/320.63
  6. Step 6: Final answer
    x = 207.13

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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.