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Finding the Fourth Proportional to 812.29, 1,218.86 and 519.95

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Solution

The fourth proportional to 812.29, 1,218.86 and 519.95 is: 780.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.29 : 1,218.86 = 519.95 : x
  2. Step 2: Convert to fraction form
    812.29/1,218.86 = 519.95/x
  3. Step 3: Cross multiply
    812.29x = 1,218.86 × 519.95
  4. Step 4: Simplify right side
    812.29x = 633,746.26
  5. Step 5: Solve for x
    x = 633,746.26/812.29
  6. Step 6: Final answer
    x = 780.20

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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.