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Finding the Fourth Proportional to 665.31, 919.15 and 619.19

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Solution

The fourth proportional to 665.31, 919.15 and 619.19 is: 855.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.31 : 919.15 = 619.19 : x
  2. Step 2: Convert to fraction form
    665.31/919.15 = 619.19/x
  3. Step 3: Cross multiply
    665.31x = 919.15 × 619.19
  4. Step 4: Simplify right side
    665.31x = 569,130.96
  5. Step 5: Solve for x
    x = 569,130.96/665.31
  6. Step 6: Final answer
    x = 855.43

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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.