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Finding the Fourth Proportional to 797.50, 1,100.79 and 640.66

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Solution

The fourth proportional to 797.50, 1,100.79 and 640.66 is: 884.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    797.50 : 1,100.79 = 640.66 : x
  2. Step 2: Convert to fraction form
    797.50/1,100.79 = 640.66/x
  3. Step 3: Cross multiply
    797.50x = 1,100.79 × 640.66
  4. Step 4: Simplify right side
    797.50x = 705,232.12
  5. Step 5: Solve for x
    x = 705,232.12/797.50
  6. Step 6: Final answer
    x = 884.30

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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.