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Finding the Fourth Proportional to 555.21, 765.79 and 389.46

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Solution

The fourth proportional to 555.21, 765.79 and 389.46 is: 537.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    555.21 : 765.79 = 389.46 : x
  2. Step 2: Convert to fraction form
    555.21/765.79 = 389.46/x
  3. Step 3: Cross multiply
    555.21x = 765.79 × 389.46
  4. Step 4: Simplify right side
    555.21x = 298,238.80
  5. Step 5: Solve for x
    x = 298,238.80/555.21
  6. Step 6: Final answer
    x = 537.17

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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.