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Finding the Fourth Proportional to 808.21, 1,115.91 and 509.59

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Solution

The fourth proportional to 808.21, 1,115.91 and 509.59 is: 703.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.21 : 1,115.91 = 509.59 : x
  2. Step 2: Convert to fraction form
    808.21/1,115.91 = 509.59/x
  3. Step 3: Cross multiply
    808.21x = 1,115.91 × 509.59
  4. Step 4: Simplify right side
    808.21x = 568,656.58
  5. Step 5: Solve for x
    x = 568,656.58/808.21
  6. Step 6: Final answer
    x = 703.60

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.