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Finding the Fourth Proportional to 722.32, 996.80 and 390.75

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Solution

The fourth proportional to 722.32, 996.80 and 390.75 is: 539.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    722.32 : 996.80 = 390.75 : x
  2. Step 2: Convert to fraction form
    722.32/996.80 = 390.75/x
  3. Step 3: Cross multiply
    722.32x = 996.80 × 390.75
  4. Step 4: Simplify right side
    722.32x = 389,499.55
  5. Step 5: Solve for x
    x = 389,499.55/722.32
  6. Step 6: Final answer
    x = 539.23

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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.