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Finding the Fourth Proportional to 717.61, 990.36 and 402.90

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Solution

The fourth proportional to 717.61, 990.36 and 402.90 is: 556.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.61 : 990.36 = 402.90 : x
  2. Step 2: Convert to fraction form
    717.61/990.36 = 402.90/x
  3. Step 3: Cross multiply
    717.61x = 990.36 × 402.90
  4. Step 4: Simplify right side
    717.61x = 399,012.41
  5. Step 5: Solve for x
    x = 399,012.41/717.61
  6. Step 6: Final answer
    x = 556.03

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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.