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Finding the Fourth Proportional to 505.20, 756.59 and 257.79

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Solution

The fourth proportional to 505.20, 756.59 and 257.79 is: 386.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.20 : 756.59 = 257.79 : x
  2. Step 2: Convert to fraction form
    505.20/756.59 = 257.79/x
  3. Step 3: Cross multiply
    505.20x = 756.59 × 257.79
  4. Step 4: Simplify right side
    505.20x = 195,042.21
  5. Step 5: Solve for x
    x = 195,042.21/505.20
  6. Step 6: Final answer
    x = 386.07

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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.