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Finding the Fourth Proportional to 280.10, 419.80 and 143.20

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Solution

The fourth proportional to 280.10, 419.80 and 143.20 is: 214.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.10 : 419.80 = 143.20 : x
  2. Step 2: Convert to fraction form
    280.10/419.80 = 143.20/x
  3. Step 3: Cross multiply
    280.10x = 419.80 × 143.20
  4. Step 4: Simplify right side
    280.10x = 60,115.36
  5. Step 5: Solve for x
    x = 60,115.36/280.10
  6. Step 6: Final answer
    x = 214.62

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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.