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Finding the Fourth Proportional to 280.55, 420.83 and 143.52

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Solution

The fourth proportional to 280.55, 420.83 and 143.52 is: 215.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.55 : 420.83 = 143.52 : x
  2. Step 2: Convert to fraction form
    280.55/420.83 = 143.52/x
  3. Step 3: Cross multiply
    280.55x = 420.83 × 143.52
  4. Step 4: Simplify right side
    280.55x = 60,397.83
  5. Step 5: Solve for x
    x = 60,397.83/280.55
  6. Step 6: Final answer
    x = 215.28

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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.