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Finding the Fourth Proportional to 279.79, 420.50 and 135.61

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Solution

The fourth proportional to 279.79, 420.50 and 135.61 is: 203.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.79 : 420.50 = 135.61 : x
  2. Step 2: Convert to fraction form
    279.79/420.50 = 135.61/x
  3. Step 3: Cross multiply
    279.79x = 420.50 × 135.61
  4. Step 4: Simplify right side
    279.79x = 57,024.01
  5. Step 5: Solve for x
    x = 57,024.01/279.79
  6. Step 6: Final answer
    x = 203.81

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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.