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Finding the Fourth Proportional to 686.85, 947.93 and 438.18

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Solution

The fourth proportional to 686.85, 947.93 and 438.18 is: 604.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.85 : 947.93 = 438.18 : x
  2. Step 2: Convert to fraction form
    686.85/947.93 = 438.18/x
  3. Step 3: Cross multiply
    686.85x = 947.93 × 438.18
  4. Step 4: Simplify right side
    686.85x = 415,361.78
  5. Step 5: Solve for x
    x = 415,361.78/686.85
  6. Step 6: Final answer
    x = 604.73

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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.