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Finding the Fourth Proportional to 807.69, 1,211.16 and 320.79

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Solution

The fourth proportional to 807.69, 1,211.16 and 320.79 is: 481.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.69 : 1,211.16 = 320.79 : x
  2. Step 2: Convert to fraction form
    807.69/1,211.16 = 320.79/x
  3. Step 3: Cross multiply
    807.69x = 1,211.16 × 320.79
  4. Step 4: Simplify right side
    807.69x = 388,528.02
  5. Step 5: Solve for x
    x = 388,528.02/807.69
  6. Step 6: Final answer
    x = 481.04

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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.