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Finding the Fourth Proportional to 665.06, 998.40 and 619.70

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Solution

The fourth proportional to 665.06, 998.40 and 619.70 is: 930.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.06 : 998.40 = 619.70 : x
  2. Step 2: Convert to fraction form
    665.06/998.40 = 619.70/x
  3. Step 3: Cross multiply
    665.06x = 998.40 × 619.70
  4. Step 4: Simplify right side
    665.06x = 618,708.48
  5. Step 5: Solve for x
    x = 618,708.48/665.06
  6. Step 6: Final answer
    x = 930.30

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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.