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Finding the Fourth Proportional to 421.84, 580.98 and 389.44

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Solution

The fourth proportional to 421.84, 580.98 and 389.44 is: 536.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.84 : 580.98 = 389.44 : x
  2. Step 2: Convert to fraction form
    421.84/580.98 = 389.44/x
  3. Step 3: Cross multiply
    421.84x = 580.98 × 389.44
  4. Step 4: Simplify right side
    421.84x = 226,256.85
  5. Step 5: Solve for x
    x = 226,256.85/421.84
  6. Step 6: Final answer
    x = 536.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.