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Finding the Fourth Proportional to 615.78, 849.38 and 394.38

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Solution

The fourth proportional to 615.78, 849.38 and 394.38 is: 543.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.78 : 849.38 = 394.38 : x
  2. Step 2: Convert to fraction form
    615.78/849.38 = 394.38/x
  3. Step 3: Cross multiply
    615.78x = 849.38 × 394.38
  4. Step 4: Simplify right side
    615.78x = 334,976.51
  5. Step 5: Solve for x
    x = 334,976.51/615.78
  6. Step 6: Final answer
    x = 543.99

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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.