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Finding the Fourth Proportional to 420.59, 629.98 and 338.99

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Solution

The fourth proportional to 420.59, 629.98 and 338.99 is: 507.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.59 : 629.98 = 338.99 : x
  2. Step 2: Convert to fraction form
    420.59/629.98 = 338.99/x
  3. Step 3: Cross multiply
    420.59x = 629.98 × 338.99
  4. Step 4: Simplify right side
    420.59x = 213,552.92
  5. Step 5: Solve for x
    x = 213,552.92/420.59
  6. Step 6: Final answer
    x = 507.74

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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.