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Finding the Fourth Proportional to 807.12, 1,210.82 and 259.47

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Solution

The fourth proportional to 807.12, 1,210.82 and 259.47 is: 389.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.12 : 1,210.82 = 259.47 : x
  2. Step 2: Convert to fraction form
    807.12/1,210.82 = 259.47/x
  3. Step 3: Cross multiply
    807.12x = 1,210.82 × 259.47
  4. Step 4: Simplify right side
    807.12x = 314,170.17
  5. Step 5: Solve for x
    x = 314,170.17/807.12
  6. Step 6: Final answer
    x = 389.25

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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.