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Finding the Fourth Proportional to 412.30, 618.71 and 239.31

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Solution

The fourth proportional to 412.30, 618.71 and 239.31 is: 359.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.30 : 618.71 = 239.31 : x
  2. Step 2: Convert to fraction form
    412.30/618.71 = 239.31/x
  3. Step 3: Cross multiply
    412.30x = 618.71 × 239.31
  4. Step 4: Simplify right side
    412.30x = 148,063.49
  5. Step 5: Solve for x
    x = 148,063.49/412.30
  6. Step 6: Final answer
    x = 359.12

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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.