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Finding the Fourth Proportional to 412.71, 619.06 and 138.80

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Solution

The fourth proportional to 412.71, 619.06 and 138.80 is: 208.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.71 : 619.06 = 138.80 : x
  2. Step 2: Convert to fraction form
    412.71/619.06 = 138.80/x
  3. Step 3: Cross multiply
    412.71x = 619.06 × 138.80
  4. Step 4: Simplify right side
    412.71x = 85,922.09
  5. Step 5: Solve for x
    x = 85,922.09/412.71
  6. Step 6: Final answer
    x = 208.19

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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.