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Finding the Fourth Proportional to 807.06, 1,209.86 and 320

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Solution

The fourth proportional to 807.06, 1,209.86 and 320 is: 479.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.06 : 1,209.86 = 320 : x
  2. Step 2: Convert to fraction form
    807.06/1,209.86 = 320/x
  3. Step 3: Cross multiply
    807.06x = 1,209.86 × 320
  4. Step 4: Simplify right side
    807.06x = 387,155.20
  5. Step 5: Solve for x
    x = 387,155.20/807.06
  6. Step 6: Final answer
    x = 479.71

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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.