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Finding the Fourth Proportional to 678.02, 935.25 and 428.90

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Solution

The fourth proportional to 678.02, 935.25 and 428.90 is: 591.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.02 : 935.25 = 428.90 : x
  2. Step 2: Convert to fraction form
    678.02/935.25 = 428.90/x
  3. Step 3: Cross multiply
    678.02x = 935.25 × 428.90
  4. Step 4: Simplify right side
    678.02x = 401,128.73
  5. Step 5: Solve for x
    x = 401,128.73/678.02
  6. Step 6: Final answer
    x = 591.62

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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.