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Finding the Fourth Proportional to 787.65, 1,087.11 and 456.11

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Solution

The fourth proportional to 787.65, 1,087.11 and 456.11 is: 629.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.65 : 1,087.11 = 456.11 : x
  2. Step 2: Convert to fraction form
    787.65/1,087.11 = 456.11/x
  3. Step 3: Cross multiply
    787.65x = 1,087.11 × 456.11
  4. Step 4: Simplify right side
    787.65x = 495,839.46
  5. Step 5: Solve for x
    x = 495,839.46/787.65
  6. Step 6: Final answer
    x = 629.52

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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.