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Finding the Fourth Proportional to 520.72, 780.87 and 312.58

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Solution

The fourth proportional to 520.72, 780.87 and 312.58 is: 468.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.72 : 780.87 = 312.58 : x
  2. Step 2: Convert to fraction form
    520.72/780.87 = 312.58/x
  3. Step 3: Cross multiply
    520.72x = 780.87 × 312.58
  4. Step 4: Simplify right side
    520.72x = 244,084.34
  5. Step 5: Solve for x
    x = 244,084.34/520.72
  6. Step 6: Final answer
    x = 468.74

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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.