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Finding the Fourth Proportional to 412.75, 619.10 and 138.77

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Solution

The fourth proportional to 412.75, 619.10 and 138.77 is: 208.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.75 : 619.10 = 138.77 : x
  2. Step 2: Convert to fraction form
    412.75/619.10 = 138.77/x
  3. Step 3: Cross multiply
    412.75x = 619.10 × 138.77
  4. Step 4: Simplify right side
    412.75x = 85,912.51
  5. Step 5: Solve for x
    x = 85,912.51/412.75
  6. Step 6: Final answer
    x = 208.15

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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.