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Finding the Fourth Proportional to 866.89, 1,300.31 and 520.31

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Solution

The fourth proportional to 866.89, 1,300.31 and 520.31 is: 780.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    866.89 : 1,300.31 = 520.31 : x
  2. Step 2: Convert to fraction form
    866.89/1,300.31 = 520.31/x
  3. Step 3: Cross multiply
    866.89x = 1,300.31 × 520.31
  4. Step 4: Simplify right side
    866.89x = 676,564.95
  5. Step 5: Solve for x
    x = 676,564.95/866.89
  6. Step 6: Final answer
    x = 780.45

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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.