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Finding the Fourth Proportional to 280.35, 420.71 and 107.15

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Solution

The fourth proportional to 280.35, 420.71 and 107.15 is: 160.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.35 : 420.71 = 107.15 : x
  2. Step 2: Convert to fraction form
    280.35/420.71 = 107.15/x
  3. Step 3: Cross multiply
    280.35x = 420.71 × 107.15
  4. Step 4: Simplify right side
    280.35x = 45,076.44
  5. Step 5: Solve for x
    x = 45,076.44/280.35
  6. Step 6: Final answer
    x = 160.79

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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.