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Finding the Fourth Proportional to 808.89, 1,213.18 and 261.07

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Solution

The fourth proportional to 808.89, 1,213.18 and 261.07 is: 391.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.89 : 1,213.18 = 261.07 : x
  2. Step 2: Convert to fraction form
    808.89/1,213.18 = 261.07/x
  3. Step 3: Cross multiply
    808.89x = 1,213.18 × 261.07
  4. Step 4: Simplify right side
    808.89x = 316,728.04
  5. Step 5: Solve for x
    x = 316,728.04/808.89
  6. Step 6: Final answer
    x = 391.56

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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.