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Finding the Fourth Proportional to 663.91, 994.95 and 420.00

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Solution

The fourth proportional to 663.91, 994.95 and 420.00 is: 629.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.91 : 994.95 = 420.00 : x
  2. Step 2: Convert to fraction form
    663.91/994.95 = 420.00/x
  3. Step 3: Cross multiply
    663.91x = 994.95 × 420.00
  4. Step 4: Simplify right side
    663.91x = 417,875.27
  5. Step 5: Solve for x
    x = 417,875.27/663.91
  6. Step 6: Final answer
    x = 629.42

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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.