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Finding the Fourth Proportional to 280.18, 420.11 and 115.55

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Solution

The fourth proportional to 280.18, 420.11 and 115.55 is: 173.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.18 : 420.11 = 115.55 : x
  2. Step 2: Convert to fraction form
    280.18/420.11 = 115.55/x
  3. Step 3: Cross multiply
    280.18x = 420.11 × 115.55
  4. Step 4: Simplify right side
    280.18x = 48,541.03
  5. Step 5: Solve for x
    x = 48,541.03/280.18
  6. Step 6: Final answer
    x = 173.25

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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.