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Finding the Fourth Proportional to 420.28, 629.43 and 214.34

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Solution

The fourth proportional to 420.28, 629.43 and 214.34 is: 321.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.28 : 629.43 = 214.34 : x
  2. Step 2: Convert to fraction form
    420.28/629.43 = 214.34/x
  3. Step 3: Cross multiply
    420.28x = 629.43 × 214.34
  4. Step 4: Simplify right side
    420.28x = 134,912.03
  5. Step 5: Solve for x
    x = 134,912.03/420.28
  6. Step 6: Final answer
    x = 321.01

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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.