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Finding the Fourth Proportional to 807.15, 1,211.01 and 320.25

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Solution

The fourth proportional to 807.15, 1,211.01 and 320.25 is: 480.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.15 : 1,211.01 = 320.25 : x
  2. Step 2: Convert to fraction form
    807.15/1,211.01 = 320.25/x
  3. Step 3: Cross multiply
    807.15x = 1,211.01 × 320.25
  4. Step 4: Simplify right side
    807.15x = 387,825.95
  5. Step 5: Solve for x
    x = 387,825.95/807.15
  6. Step 6: Final answer
    x = 480.49

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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.