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Finding the Fourth Proportional to 818.21, 1,128.04 and 660.66

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Solution

The fourth proportional to 818.21, 1,128.04 and 660.66 is: 910.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.21 : 1,128.04 = 660.66 : x
  2. Step 2: Convert to fraction form
    818.21/1,128.04 = 660.66/x
  3. Step 3: Cross multiply
    818.21x = 1,128.04 × 660.66
  4. Step 4: Simplify right side
    818.21x = 745,250.91
  5. Step 5: Solve for x
    x = 745,250.91/818.21
  6. Step 6: Final answer
    x = 910.83

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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.