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Finding the Fourth Proportional to 808.86, 1,213.30 and 520.50

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Solution

The fourth proportional to 808.86, 1,213.30 and 520.50 is: 780.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.86 : 1,213.30 = 520.50 : x
  2. Step 2: Convert to fraction form
    808.86/1,213.30 = 520.50/x
  3. Step 3: Cross multiply
    808.86x = 1,213.30 × 520.50
  4. Step 4: Simplify right side
    808.86x = 631,522.65
  5. Step 5: Solve for x
    x = 631,522.65/808.86
  6. Step 6: Final answer
    x = 780.76

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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.