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Finding the Fourth Proportional to 284.89, 427.50 and 128.71

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Solution

The fourth proportional to 284.89, 427.50 and 128.71 is: 193.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.89 : 427.50 = 128.71 : x
  2. Step 2: Convert to fraction form
    284.89/427.50 = 128.71/x
  3. Step 3: Cross multiply
    284.89x = 427.50 × 128.71
  4. Step 4: Simplify right side
    284.89x = 55,023.53
  5. Step 5: Solve for x
    x = 55,023.53/284.89
  6. Step 6: Final answer
    x = 193.14

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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.