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Finding the Fourth Proportional to 520.15, 780.04 and 211.93

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Solution

The fourth proportional to 520.15, 780.04 and 211.93 is: 317.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.15 : 780.04 = 211.93 : x
  2. Step 2: Convert to fraction form
    520.15/780.04 = 211.93/x
  3. Step 3: Cross multiply
    520.15x = 780.04 × 211.93
  4. Step 4: Simplify right side
    520.15x = 165,313.88
  5. Step 5: Solve for x
    x = 165,313.88/520.15
  6. Step 6: Final answer
    x = 317.82

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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.