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Finding the Fourth Proportional to 280.78, 387.39 and 175.87

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Solution

The fourth proportional to 280.78, 387.39 and 175.87 is: 242.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.78 : 387.39 = 175.87 : x
  2. Step 2: Convert to fraction form
    280.78/387.39 = 175.87/x
  3. Step 3: Cross multiply
    280.78x = 387.39 × 175.87
  4. Step 4: Simplify right side
    280.78x = 68,130.28
  5. Step 5: Solve for x
    x = 68,130.28/280.78
  6. Step 6: Final answer
    x = 242.65

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.