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Finding the Fourth Proportional to 420.17, 629.87 and 189.18

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Solution

The fourth proportional to 420.17, 629.87 and 189.18 is: 283.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.17 : 629.87 = 189.18 : x
  2. Step 2: Convert to fraction form
    420.17/629.87 = 189.18/x
  3. Step 3: Cross multiply
    420.17x = 629.87 × 189.18
  4. Step 4: Simplify right side
    420.17x = 119,158.81
  5. Step 5: Solve for x
    x = 119,158.81/420.17
  6. Step 6: Final answer
    x = 283.60

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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.