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Finding the Fourth Proportional to 717.60, 990.36 and 407.12

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Solution

The fourth proportional to 717.60, 990.36 and 407.12 is: 561.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.60 : 990.36 = 407.12 : x
  2. Step 2: Convert to fraction form
    717.60/990.36 = 407.12/x
  3. Step 3: Cross multiply
    717.60x = 990.36 × 407.12
  4. Step 4: Simplify right side
    717.60x = 403,195.36
  5. Step 5: Solve for x
    x = 403,195.36/717.60
  6. Step 6: Final answer
    x = 561.87

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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.