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Finding the Fourth Proportional to 438.28, 654.26 and 380.90

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Solution

The fourth proportional to 438.28, 654.26 and 380.90 is: 568.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.28 : 654.26 = 380.90 : x
  2. Step 2: Convert to fraction form
    438.28/654.26 = 380.90/x
  3. Step 3: Cross multiply
    438.28x = 654.26 × 380.90
  4. Step 4: Simplify right side
    438.28x = 249,207.63
  5. Step 5: Solve for x
    x = 249,207.63/438.28
  6. Step 6: Final answer
    x = 568.60

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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.