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Finding the Fourth Proportional to 280.15, 420.07 and 106.78

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Solution

The fourth proportional to 280.15, 420.07 and 106.78 is: 160.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.15 : 420.07 = 106.78 : x
  2. Step 2: Convert to fraction form
    280.15/420.07 = 106.78/x
  3. Step 3: Cross multiply
    280.15x = 420.07 × 106.78
  4. Step 4: Simplify right side
    280.15x = 44,855.07
  5. Step 5: Solve for x
    x = 44,855.07/280.15
  6. Step 6: Final answer
    x = 160.11

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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.