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Finding the Fourth Proportional to 608.78, 840.23 and 387.68

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Solution

The fourth proportional to 608.78, 840.23 and 387.68 is: 535.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.78 : 840.23 = 387.68 : x
  2. Step 2: Convert to fraction form
    608.78/840.23 = 387.68/x
  3. Step 3: Cross multiply
    608.78x = 840.23 × 387.68
  4. Step 4: Simplify right side
    608.78x = 325,734.23
  5. Step 5: Solve for x
    x = 325,734.23/608.78
  6. Step 6: Final answer
    x = 535.07

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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.