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Finding the Fourth Proportional to 678.28, 935.94 and 394.72

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Solution

The fourth proportional to 678.28, 935.94 and 394.72 is: 544.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.28 : 935.94 = 394.72 : x
  2. Step 2: Convert to fraction form
    678.28/935.94 = 394.72/x
  3. Step 3: Cross multiply
    678.28x = 935.94 × 394.72
  4. Step 4: Simplify right side
    678.28x = 369,434.24
  5. Step 5: Solve for x
    x = 369,434.24/678.28
  6. Step 6: Final answer
    x = 544.66

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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.