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Finding the Fourth Proportional to 505.28, 755.66 and 380.30

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Solution

The fourth proportional to 505.28, 755.66 and 380.30 is: 568.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.28 : 755.66 = 380.30 : x
  2. Step 2: Convert to fraction form
    505.28/755.66 = 380.30/x
  3. Step 3: Cross multiply
    505.28x = 755.66 × 380.30
  4. Step 4: Simplify right side
    505.28x = 287,374.67
  5. Step 5: Solve for x
    x = 287,374.67/505.28
  6. Step 6: Final answer
    x = 568.74

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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.