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Finding the Fourth Proportional to 807.36, 1,209.84 and 421.44

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Solution

The fourth proportional to 807.36, 1,209.84 and 421.44 is: 631.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.36 : 1,209.84 = 421.44 : x
  2. Step 2: Convert to fraction form
    807.36/1,209.84 = 421.44/x
  3. Step 3: Cross multiply
    807.36x = 1,209.84 × 421.44
  4. Step 4: Simplify right side
    807.36x = 509,874.97
  5. Step 5: Solve for x
    x = 509,874.97/807.36
  6. Step 6: Final answer
    x = 631.53

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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.