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Finding the Fourth Proportional to 665.40, 998.21 and 340.66

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Solution

The fourth proportional to 665.40, 998.21 and 340.66 is: 511.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.40 : 998.21 = 340.66 : x
  2. Step 2: Convert to fraction form
    665.40/998.21 = 340.66/x
  3. Step 3: Cross multiply
    665.40x = 998.21 × 340.66
  4. Step 4: Simplify right side
    665.40x = 340,050.22
  5. Step 5: Solve for x
    x = 340,050.22/665.40
  6. Step 6: Final answer
    x = 511.05

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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.