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Finding the Fourth Proportional to 787.56, 1,181.49 and 319.05

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Solution

The fourth proportional to 787.56, 1,181.49 and 319.05 is: 478.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.56 : 1,181.49 = 319.05 : x
  2. Step 2: Convert to fraction form
    787.56/1,181.49 = 319.05/x
  3. Step 3: Cross multiply
    787.56x = 1,181.49 × 319.05
  4. Step 4: Simplify right side
    787.56x = 376,954.38
  5. Step 5: Solve for x
    x = 376,954.38/787.56
  6. Step 6: Final answer
    x = 478.64

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.