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Finding the Fourth Proportional to 528.30, 790.89 and 391.95

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Solution

The fourth proportional to 528.30, 790.89 and 391.95 is: 586.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.30 : 790.89 = 391.95 : x
  2. Step 2: Convert to fraction form
    528.30/790.89 = 391.95/x
  3. Step 3: Cross multiply
    528.30x = 790.89 × 391.95
  4. Step 4: Simplify right side
    528.30x = 309,989.34
  5. Step 5: Solve for x
    x = 309,989.34/528.30
  6. Step 6: Final answer
    x = 586.77

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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.