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Finding the Fourth Proportional to 663.90, 996.30 and 390.37

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Solution

The fourth proportional to 663.90, 996.30 and 390.37 is: 585.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.90 : 996.30 = 390.37 : x
  2. Step 2: Convert to fraction form
    663.90/996.30 = 390.37/x
  3. Step 3: Cross multiply
    663.90x = 996.30 × 390.37
  4. Step 4: Simplify right side
    663.90x = 388,925.01
  5. Step 5: Solve for x
    x = 388,925.01/663.90
  6. Step 6: Final answer
    x = 585.82

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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.