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Finding the Fourth Proportional to 280.85, 421.25 and 107.51

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Solution

The fourth proportional to 280.85, 421.25 and 107.51 is: 161.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.85 : 421.25 = 107.51 : x
  2. Step 2: Convert to fraction form
    280.85/421.25 = 107.51/x
  3. Step 3: Cross multiply
    280.85x = 421.25 × 107.51
  4. Step 4: Simplify right side
    280.85x = 45,285.94
  5. Step 5: Solve for x
    x = 45,285.94/280.85
  6. Step 6: Final answer
    x = 161.25

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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.