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Finding the Fourth Proportional to 668.28, 1,003.14 and 278.55

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Solution

The fourth proportional to 668.28, 1,003.14 and 278.55 is: 418.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.28 : 1,003.14 = 278.55 : x
  2. Step 2: Convert to fraction form
    668.28/1,003.14 = 278.55/x
  3. Step 3: Cross multiply
    668.28x = 1,003.14 × 278.55
  4. Step 4: Simplify right side
    668.28x = 279,424.65
  5. Step 5: Solve for x
    x = 279,424.65/668.28
  6. Step 6: Final answer
    x = 418.13

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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.