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Finding the Fourth Proportional to 438.41, 654.51 and 389.81

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Solution

The fourth proportional to 438.41, 654.51 and 389.81 is: 581.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.41 : 654.51 = 389.81 : x
  2. Step 2: Convert to fraction form
    438.41/654.51 = 389.81/x
  3. Step 3: Cross multiply
    438.41x = 654.51 × 389.81
  4. Step 4: Simplify right side
    438.41x = 255,135.45
  5. Step 5: Solve for x
    x = 255,135.45/438.41
  6. Step 6: Final answer
    x = 581.95

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.