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Finding the Fourth Proportional to 407.83, 611.39 and 212.72

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Solution

The fourth proportional to 407.83, 611.39 and 212.72 is: 318.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.83 : 611.39 = 212.72 : x
  2. Step 2: Convert to fraction form
    407.83/611.39 = 212.72/x
  3. Step 3: Cross multiply
    407.83x = 611.39 × 212.72
  4. Step 4: Simplify right side
    407.83x = 130,054.88
  5. Step 5: Solve for x
    x = 130,054.88/407.83
  6. Step 6: Final answer
    x = 318.89

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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.