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Finding the Fourth Proportional to 555.30, 765.81 and 380.70

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Solution

The fourth proportional to 555.30, 765.81 and 380.70 is: 525.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    555.30 : 765.81 = 380.70 : x
  2. Step 2: Convert to fraction form
    555.30/765.81 = 380.70/x
  3. Step 3: Cross multiply
    555.30x = 765.81 × 380.70
  4. Step 4: Simplify right side
    555.30x = 291,543.87
  5. Step 5: Solve for x
    x = 291,543.87/555.30
  6. Step 6: Final answer
    x = 525.02

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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.