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Finding the Fourth Proportional to 805.59, 1,110.63 and 640.35

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Solution

The fourth proportional to 805.59, 1,110.63 and 640.35 is: 882.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.59 : 1,110.63 = 640.35 : x
  2. Step 2: Convert to fraction form
    805.59/1,110.63 = 640.35/x
  3. Step 3: Cross multiply
    805.59x = 1,110.63 × 640.35
  4. Step 4: Simplify right side
    805.59x = 711,191.92
  5. Step 5: Solve for x
    x = 711,191.92/805.59
  6. Step 6: Final answer
    x = 882.82

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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.