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Finding the Fourth Proportional to 505.77, 758.67 and 390.39

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Solution

The fourth proportional to 505.77, 758.67 and 390.39 is: 585.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.77 : 758.67 = 390.39 : x
  2. Step 2: Convert to fraction form
    505.77/758.67 = 390.39/x
  3. Step 3: Cross multiply
    505.77x = 758.67 × 390.39
  4. Step 4: Simplify right side
    505.77x = 296,177.18
  5. Step 5: Solve for x
    x = 296,177.18/505.77
  6. Step 6: Final answer
    x = 585.60

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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.