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Finding the Fourth Proportional to 803.70, 1,108.17 and 664.20

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Solution

The fourth proportional to 803.70, 1,108.17 and 664.20 is: 915.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    803.70 : 1,108.17 = 664.20 : x
  2. Step 2: Convert to fraction form
    803.70/1,108.17 = 664.20/x
  3. Step 3: Cross multiply
    803.70x = 1,108.17 × 664.20
  4. Step 4: Simplify right side
    803.70x = 736,046.51
  5. Step 5: Solve for x
    x = 736,046.51/803.70
  6. Step 6: Final answer
    x = 915.82

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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.