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Finding the Fourth Proportional to 420.14, 629.73 and 189.15

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Solution

The fourth proportional to 420.14, 629.73 and 189.15 is: 283.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.14 : 629.73 = 189.15 : x
  2. Step 2: Convert to fraction form
    420.14/629.73 = 189.15/x
  3. Step 3: Cross multiply
    420.14x = 629.73 × 189.15
  4. Step 4: Simplify right side
    420.14x = 119,113.43
  5. Step 5: Solve for x
    x = 119,113.43/420.14
  6. Step 6: Final answer
    x = 283.51

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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.