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Finding the Fourth Proportional to 717.89, 991.38 and 618.71

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Solution

The fourth proportional to 717.89, 991.38 and 618.71 is: 854.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.89 : 991.38 = 618.71 : x
  2. Step 2: Convert to fraction form
    717.89/991.38 = 618.71/x
  3. Step 3: Cross multiply
    717.89x = 991.38 × 618.71
  4. Step 4: Simplify right side
    717.89x = 613,379.20
  5. Step 5: Solve for x
    x = 613,379.20/717.89
  6. Step 6: Final answer
    x = 854.43

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1.5x scale

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.