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Finding the Fourth Proportional to 407.80, 609.37 and 309.76

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Solution

The fourth proportional to 407.80, 609.37 and 309.76 is: 462.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.80 : 609.37 = 309.76 : x
  2. Step 2: Convert to fraction form
    407.80/609.37 = 309.76/x
  3. Step 3: Cross multiply
    407.80x = 609.37 × 309.76
  4. Step 4: Simplify right side
    407.80x = 188,758.45
  5. Step 5: Solve for x
    x = 188,758.45/407.80
  6. Step 6: Final answer
    x = 462.87

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.