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Finding the Fourth Proportional to 520.42, 780.32 and 259.84

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Solution

The fourth proportional to 520.42, 780.32 and 259.84 is: 389.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.42 : 780.32 = 259.84 : x
  2. Step 2: Convert to fraction form
    520.42/780.32 = 259.84/x
  3. Step 3: Cross multiply
    520.42x = 780.32 × 259.84
  4. Step 4: Simplify right side
    520.42x = 202,758.35
  5. Step 5: Solve for x
    x = 202,758.35/520.42
  6. Step 6: Final answer
    x = 389.61

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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.