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Finding the Fourth Proportional to 805.40, 1,111.32 and 490.50

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Solution

The fourth proportional to 805.40, 1,111.32 and 490.50 is: 676.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.40 : 1,111.32 = 490.50 : x
  2. Step 2: Convert to fraction form
    805.40/1,111.32 = 490.50/x
  3. Step 3: Cross multiply
    805.40x = 1,111.32 × 490.50
  4. Step 4: Simplify right side
    805.40x = 545,102.46
  5. Step 5: Solve for x
    x = 545,102.46/805.40
  6. Step 6: Final answer
    x = 676.81

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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.