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Finding the Fourth Proportional to 506.71, 698.90 and 388.70

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Solution

The fourth proportional to 506.71, 698.90 and 388.70 is: 536.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    506.71 : 698.90 = 388.70 : x
  2. Step 2: Convert to fraction form
    506.71/698.90 = 388.70/x
  3. Step 3: Cross multiply
    506.71x = 698.90 × 388.70
  4. Step 4: Simplify right side
    506.71x = 271,662.43
  5. Step 5: Solve for x
    x = 271,662.43/506.71
  6. Step 6: Final answer
    x = 536.13

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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.