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Finding the Fourth Proportional to 385.79, 578.55 and 125.72

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Solution

The fourth proportional to 385.79, 578.55 and 125.72 is: 188.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.79 : 578.55 = 125.72 : x
  2. Step 2: Convert to fraction form
    385.79/578.55 = 125.72/x
  3. Step 3: Cross multiply
    385.79x = 578.55 × 125.72
  4. Step 4: Simplify right side
    385.79x = 72,736.75
  5. Step 5: Solve for x
    x = 72,736.75/385.79
  6. Step 6: Final answer
    x = 188.54

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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.