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Finding the Fourth Proportional to 787.02, 1,085.30 and 646.99

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Solution

The fourth proportional to 787.02, 1,085.30 and 646.99 is: 892.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.02 : 1,085.30 = 646.99 : x
  2. Step 2: Convert to fraction form
    787.02/1,085.30 = 646.99/x
  3. Step 3: Cross multiply
    787.02x = 1,085.30 × 646.99
  4. Step 4: Simplify right side
    787.02x = 702,174.73
  5. Step 5: Solve for x
    x = 702,174.73/787.02
  6. Step 6: Final answer
    x = 892.20

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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.