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Finding the Fourth Proportional to 631.20, 869.64 and 555.84

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Solution

The fourth proportional to 631.20, 869.64 and 555.84 is: 765.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.20 : 869.64 = 555.84 : x
  2. Step 2: Convert to fraction form
    631.20/869.64 = 555.84/x
  3. Step 3: Cross multiply
    631.20x = 869.64 × 555.84
  4. Step 4: Simplify right side
    631.20x = 483,380.70
  5. Step 5: Solve for x
    x = 483,380.70/631.20
  6. Step 6: Final answer
    x = 765.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.