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Finding the Fourth Proportional to 729.80, 1,095.10 and 405.12

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Solution

The fourth proportional to 729.80, 1,095.10 and 405.12 is: 607.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    729.80 : 1,095.10 = 405.12 : x
  2. Step 2: Convert to fraction form
    729.80/1,095.10 = 405.12/x
  3. Step 3: Cross multiply
    729.80x = 1,095.10 × 405.12
  4. Step 4: Simplify right side
    729.80x = 443,646.91
  5. Step 5: Solve for x
    x = 443,646.91/729.80
  6. Step 6: Final answer
    x = 607.90

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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.