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Finding the Fourth Proportional to 717.30, 990.09 and 521.10

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Solution

The fourth proportional to 717.30, 990.09 and 521.10 is: 719.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    717.30 : 990.09 = 521.10 : x
  2. Step 2: Convert to fraction form
    717.30/990.09 = 521.10/x
  3. Step 3: Cross multiply
    717.30x = 990.09 × 521.10
  4. Step 4: Simplify right side
    717.30x = 515,935.90
  5. Step 5: Solve for x
    x = 515,935.90/717.30
  6. Step 6: Final answer
    x = 719.27

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Double scale
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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.