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Finding the Fourth Proportional to 608.81, 840.29 and 387.71

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Solution

The fourth proportional to 608.81, 840.29 and 387.71 is: 535.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.81 : 840.29 = 387.71 : x
  2. Step 2: Convert to fraction form
    608.81/840.29 = 387.71/x
  3. Step 3: Cross multiply
    608.81x = 840.29 × 387.71
  4. Step 4: Simplify right side
    608.81x = 325,791.91
  5. Step 5: Solve for x
    x = 325,791.91/608.81
  6. Step 6: Final answer
    x = 535.13

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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.