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Finding the Fourth Proportional to 612.31, 918.36 and 278.68

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Solution

The fourth proportional to 612.31, 918.36 and 278.68 is: 417.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.31 : 918.36 = 278.68 : x
  2. Step 2: Convert to fraction form
    612.31/918.36 = 278.68/x
  3. Step 3: Cross multiply
    612.31x = 918.36 × 278.68
  4. Step 4: Simplify right side
    612.31x = 255,930.05
  5. Step 5: Solve for x
    x = 255,930.05/612.31
  6. Step 6: Final answer
    x = 417.97

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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.