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Finding the Fourth Proportional to 420.40, 629.62 and 304.36

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Solution

The fourth proportional to 420.40, 629.62 and 304.36 is: 455.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.40 : 629.62 = 304.36 : x
  2. Step 2: Convert to fraction form
    420.40/629.62 = 304.36/x
  3. Step 3: Cross multiply
    420.40x = 629.62 × 304.36
  4. Step 4: Simplify right side
    420.40x = 191,631.14
  5. Step 5: Solve for x
    x = 191,631.14/420.40
  6. Step 6: Final answer
    x = 455.83

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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.