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Finding the Fourth Proportional to 808.10, 1,211.34 and 259.88

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Solution

The fourth proportional to 808.10, 1,211.34 and 259.88 is: 389.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.10 : 1,211.34 = 259.88 : x
  2. Step 2: Convert to fraction form
    808.10/1,211.34 = 259.88/x
  3. Step 3: Cross multiply
    808.10x = 1,211.34 × 259.88
  4. Step 4: Simplify right side
    808.10x = 314,803.04
  5. Step 5: Solve for x
    x = 314,803.04/808.10
  6. Step 6: Final answer
    x = 389.56

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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.