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Finding the Fourth Proportional to 661.28, 994.20 and 618.45

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Solution

The fourth proportional to 661.28, 994.20 and 618.45 is: 929.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.28 : 994.20 = 618.45 : x
  2. Step 2: Convert to fraction form
    661.28/994.20 = 618.45/x
  3. Step 3: Cross multiply
    661.28x = 994.20 × 618.45
  4. Step 4: Simplify right side
    661.28x = 614,862.99
  5. Step 5: Solve for x
    x = 614,862.99/661.28
  6. Step 6: Final answer
    x = 929.81

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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.