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Finding the Fourth Proportional to 280.00, 420.05 and 74.59

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Solution

The fourth proportional to 280.00, 420.05 and 74.59 is: 111.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.00 : 420.05 = 74.59 : x
  2. Step 2: Convert to fraction form
    280.00/420.05 = 74.59/x
  3. Step 3: Cross multiply
    280.00x = 420.05 × 74.59
  4. Step 4: Simplify right side
    280.00x = 31,330.35
  5. Step 5: Solve for x
    x = 31,330.35/280.00
  6. Step 6: Final answer
    x = 111.89

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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.