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Finding the Fourth Proportional to 520.59, 780.89 and 135.84

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Solution

The fourth proportional to 520.59, 780.89 and 135.84 is: 203.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.59 : 780.89 = 135.84 : x
  2. Step 2: Convert to fraction form
    520.59/780.89 = 135.84/x
  3. Step 3: Cross multiply
    520.59x = 780.89 × 135.84
  4. Step 4: Simplify right side
    520.59x = 106,079.11
  5. Step 5: Solve for x
    x = 106,079.11/520.59
  6. Step 6: Final answer
    x = 203.77

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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.