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Finding the Fourth Proportional to 807.65, 1,211.47 and 259.84

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Solution

The fourth proportional to 807.65, 1,211.47 and 259.84 is: 389.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.65 : 1,211.47 = 259.84 : x
  2. Step 2: Convert to fraction form
    807.65/1,211.47 = 259.84/x
  3. Step 3: Cross multiply
    807.65x = 1,211.47 × 259.84
  4. Step 4: Simplify right side
    807.65x = 314,784.69
  5. Step 5: Solve for x
    x = 314,784.69/807.65
  6. Step 6: Final answer
    x = 389.75

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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.