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Finding the Fourth Proportional to 665.30, 996.58 and 390.57

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Solution

The fourth proportional to 665.30, 996.58 and 390.57 is: 585.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.30 : 996.58 = 390.57 : x
  2. Step 2: Convert to fraction form
    665.30/996.58 = 390.57/x
  3. Step 3: Cross multiply
    665.30x = 996.58 × 390.57
  4. Step 4: Simplify right side
    665.30x = 389,231.00
  5. Step 5: Solve for x
    x = 389,231.00/665.30
  6. Step 6: Final answer
    x = 585.04

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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.