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Finding the Fourth Proportional to 807.28, 1,211.19 and 320.47

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Solution

The fourth proportional to 807.28, 1,211.19 and 320.47 is: 480.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.28 : 1,211.19 = 320.47 : x
  2. Step 2: Convert to fraction form
    807.28/1,211.19 = 320.47/x
  3. Step 3: Cross multiply
    807.28x = 1,211.19 × 320.47
  4. Step 4: Simplify right side
    807.28x = 388,150.06
  5. Step 5: Solve for x
    x = 388,150.06/807.28
  6. Step 6: Final answer
    x = 480.81

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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.