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Finding the Fourth Proportional to 808.19, 1,209.90 and 499.05

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Solution

The fourth proportional to 808.19, 1,209.90 and 499.05 is: 747.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    808.19 : 1,209.90 = 499.05 : x
  2. Step 2: Convert to fraction form
    808.19/1,209.90 = 499.05/x
  3. Step 3: Cross multiply
    808.19x = 1,209.90 × 499.05
  4. Step 4: Simplify right side
    808.19x = 603,798.72
  5. Step 5: Solve for x
    x = 603,798.72/808.19
  6. Step 6: Final answer
    x = 747.10

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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.