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Finding the Fourth Proportional to 407.70, 611.57 and 339.71

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Solution

The fourth proportional to 407.70, 611.57 and 339.71 is: 509.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.70 : 611.57 = 339.71 : x
  2. Step 2: Convert to fraction form
    407.70/611.57 = 339.71/x
  3. Step 3: Cross multiply
    407.70x = 611.57 × 339.71
  4. Step 4: Simplify right side
    407.70x = 207,754.24
  5. Step 5: Solve for x
    x = 207,754.24/407.70
  6. Step 6: Final answer
    x = 509.58

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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.