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Finding the Fourth Proportional to 612.09, 844.37 and 390.81

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Solution

The fourth proportional to 612.09, 844.37 and 390.81 is: 539.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.09 : 844.37 = 390.81 : x
  2. Step 2: Convert to fraction form
    612.09/844.37 = 390.81/x
  3. Step 3: Cross multiply
    612.09x = 844.37 × 390.81
  4. Step 4: Simplify right side
    612.09x = 329,988.24
  5. Step 5: Solve for x
    x = 329,988.24/612.09
  6. Step 6: Final answer
    x = 539.12

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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.