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Finding the Fourth Proportional to 906.71, 1,359.30 and 420.11

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Solution

The fourth proportional to 906.71, 1,359.30 and 420.11 is: 629.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    906.71 : 1,359.30 = 420.11 : x
  2. Step 2: Convert to fraction form
    906.71/1,359.30 = 420.11/x
  3. Step 3: Cross multiply
    906.71x = 1,359.30 × 420.11
  4. Step 4: Simplify right side
    906.71x = 571,048.73
  5. Step 5: Solve for x
    x = 571,048.73/906.71
  6. Step 6: Final answer
    x = 629.81

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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.