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Finding the Fourth Proportional to 608.40, 838.92 and 387

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Solution

The fourth proportional to 608.40, 838.92 and 387 is: 533.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.40 : 838.92 = 387 : x
  2. Step 2: Convert to fraction form
    608.40/838.92 = 387/x
  3. Step 3: Cross multiply
    608.40x = 838.92 × 387
  4. Step 4: Simplify right side
    608.40x = 324,662.04
  5. Step 5: Solve for x
    x = 324,662.04/608.40
  6. Step 6: Final answer
    x = 533.63

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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.