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Finding the Fourth Proportional to 787.05, 1,085.84 and 637.61

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Solution

The fourth proportional to 787.05, 1,085.84 and 637.61 is: 879.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    787.05 : 1,085.84 = 637.61 : x
  2. Step 2: Convert to fraction form
    787.05/1,085.84 = 637.61/x
  3. Step 3: Cross multiply
    787.05x = 1,085.84 × 637.61
  4. Step 4: Simplify right side
    787.05x = 692,336.22
  5. Step 5: Solve for x
    x = 692,336.22/787.05
  6. Step 6: Final answer
    x = 879.66

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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.