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Finding the Fourth Proportional to 280.10, 386.52 and 155.70

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Solution

The fourth proportional to 280.10, 386.52 and 155.70 is: 214.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.10 : 386.52 = 155.70 : x
  2. Step 2: Convert to fraction form
    280.10/386.52 = 155.70/x
  3. Step 3: Cross multiply
    280.10x = 386.52 × 155.70
  4. Step 4: Simplify right side
    280.10x = 60,181.16
  5. Step 5: Solve for x
    x = 60,181.16/280.10
  6. Step 6: Final answer
    x = 214.86

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.