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Finding the Fourth Proportional to 665.70, 998.10 and 340.80

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Solution

The fourth proportional to 665.70, 998.10 and 340.80 is: 510.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.70 : 998.10 = 340.80 : x
  2. Step 2: Convert to fraction form
    665.70/998.10 = 340.80/x
  3. Step 3: Cross multiply
    665.70x = 998.10 × 340.80
  4. Step 4: Simplify right side
    665.70x = 340,152.48
  5. Step 5: Solve for x
    x = 340,152.48/665.70
  6. Step 6: Final answer
    x = 510.97

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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.