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Finding the Fourth Proportional to 420.18, 629.80 and 214.14

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Solution

The fourth proportional to 420.18, 629.80 and 214.14 is: 320.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.18 : 629.80 = 214.14 : x
  2. Step 2: Convert to fraction form
    420.18/629.80 = 214.14/x
  3. Step 3: Cross multiply
    420.18x = 629.80 × 214.14
  4. Step 4: Simplify right side
    420.18x = 134,865.37
  5. Step 5: Solve for x
    x = 134,865.37/420.18
  6. Step 6: Final answer
    x = 320.97

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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.