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Finding the Fourth Proportional to 520.70, 780.44 and 289.53

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Solution

The fourth proportional to 520.70, 780.44 and 289.53 is: 433.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.70 : 780.44 = 289.53 : x
  2. Step 2: Convert to fraction form
    520.70/780.44 = 289.53/x
  3. Step 3: Cross multiply
    520.70x = 780.44 × 289.53
  4. Step 4: Simplify right side
    520.70x = 225,959.35
  5. Step 5: Solve for x
    x = 225,959.35/520.70
  6. Step 6: Final answer
    x = 433.96

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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.