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Finding the Fourth Proportional to 866.96, 1,300.80 and 521

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Solution

The fourth proportional to 866.96, 1,300.80 and 521 is: 781.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    866.96 : 1,300.80 = 521 : x
  2. Step 2: Convert to fraction form
    866.96/1,300.80 = 521/x
  3. Step 3: Cross multiply
    866.96x = 1,300.80 × 521
  4. Step 4: Simplify right side
    866.96x = 677,716.80
  5. Step 5: Solve for x
    x = 677,716.80/866.96
  6. Step 6: Final answer
    x = 781.72

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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.