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Finding the Fourth Proportional to 280.88, 421.28 and 95.78

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Solution

The fourth proportional to 280.88, 421.28 and 95.78 is: 143.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.88 : 421.28 = 95.78 : x
  2. Step 2: Convert to fraction form
    280.88/421.28 = 95.78/x
  3. Step 3: Cross multiply
    280.88x = 421.28 × 95.78
  4. Step 4: Simplify right side
    280.88x = 40,350.20
  5. Step 5: Solve for x
    x = 40,350.20/280.88
  6. Step 6: Final answer
    x = 143.66

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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.