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Finding the Fourth Proportional to 280.02, 420.28 and 143.16

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Solution

The fourth proportional to 280.02, 420.28 and 143.16 is: 214.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.02 : 420.28 = 143.16 : x
  2. Step 2: Convert to fraction form
    280.02/420.28 = 143.16/x
  3. Step 3: Cross multiply
    280.02x = 420.28 × 143.16
  4. Step 4: Simplify right side
    280.02x = 60,164.47
  5. Step 5: Solve for x
    x = 60,164.47/280.02
  6. Step 6: Final answer
    x = 214.86

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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.