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Finding the Fourth Proportional to 412.59, 618.87 and 138.68

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Solution

The fourth proportional to 412.59, 618.87 and 138.68 is: 208.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.59 : 618.87 = 138.68 : x
  2. Step 2: Convert to fraction form
    412.59/618.87 = 138.68/x
  3. Step 3: Cross multiply
    412.59x = 618.87 × 138.68
  4. Step 4: Simplify right side
    412.59x = 85,821.80
  5. Step 5: Solve for x
    x = 85,821.80/412.59
  6. Step 6: Final answer
    x = 208.01

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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.