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Finding the Fourth Proportional to 412.94, 619.40 and 138.89

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Solution

The fourth proportional to 412.94, 619.40 and 138.89 is: 208.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.94 : 619.40 = 138.89 : x
  2. Step 2: Convert to fraction form
    412.94/619.40 = 138.89/x
  3. Step 3: Cross multiply
    412.94x = 619.40 × 138.89
  4. Step 4: Simplify right side
    412.94x = 86,024.67
  5. Step 5: Solve for x
    x = 86,024.67/412.94
  6. Step 6: Final answer
    x = 208.32

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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.