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Finding the Fourth Proportional to 660.76, 991.12 and 372.20

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Solution

The fourth proportional to 660.76, 991.12 and 372.20 is: 558.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.76 : 991.12 = 372.20 : x
  2. Step 2: Convert to fraction form
    660.76/991.12 = 372.20/x
  3. Step 3: Cross multiply
    660.76x = 991.12 × 372.20
  4. Step 4: Simplify right side
    660.76x = 368,894.86
  5. Step 5: Solve for x
    x = 368,894.86/660.76
  6. Step 6: Final answer
    x = 558.29

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.