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Finding the Fourth Proportional to 478.21, 717.42 and 189.64

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Solution

The fourth proportional to 478.21, 717.42 and 189.64 is: 284.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.21 : 717.42 = 189.64 : x
  2. Step 2: Convert to fraction form
    478.21/717.42 = 189.64/x
  3. Step 3: Cross multiply
    478.21x = 717.42 × 189.64
  4. Step 4: Simplify right side
    478.21x = 136,051.53
  5. Step 5: Solve for x
    x = 136,051.53/478.21
  6. Step 6: Final answer
    x = 284.50

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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.