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Finding the Fourth Proportional to 720.09, 1,079.12 and 308.81

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Solution

The fourth proportional to 720.09, 1,079.12 and 308.81 is: 462.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    720.09 : 1,079.12 = 308.81 : x
  2. Step 2: Convert to fraction form
    720.09/1,079.12 = 308.81/x
  3. Step 3: Cross multiply
    720.09x = 1,079.12 × 308.81
  4. Step 4: Simplify right side
    720.09x = 333,246.52
  5. Step 5: Solve for x
    x = 333,246.52/720.09
  6. Step 6: Final answer
    x = 462.78

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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.