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Finding the Fourth Proportional to 421.13, 630.78 and 204.25

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Solution

The fourth proportional to 421.13, 630.78 and 204.25 is: 305.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.13 : 630.78 = 204.25 : x
  2. Step 2: Convert to fraction form
    421.13/630.78 = 204.25/x
  3. Step 3: Cross multiply
    421.13x = 630.78 × 204.25
  4. Step 4: Simplify right side
    421.13x = 128,836.82
  5. Step 5: Solve for x
    x = 128,836.82/421.13
  6. Step 6: Final answer
    x = 305.93

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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.