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Finding the Fourth Proportional to 505.31, 757.21 and 261.51

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Solution

The fourth proportional to 505.31, 757.21 and 261.51 is: 391.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.31 : 757.21 = 261.51 : x
  2. Step 2: Convert to fraction form
    505.31/757.21 = 261.51/x
  3. Step 3: Cross multiply
    505.31x = 757.21 × 261.51
  4. Step 4: Simplify right side
    505.31x = 198,017.99
  5. Step 5: Solve for x
    x = 198,017.99/505.31
  6. Step 6: Final answer
    x = 391.87

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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.