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Finding the Fourth Proportional to 620.25, 855.96 and 387.51

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Solution

The fourth proportional to 620.25, 855.96 and 387.51 is: 534.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.25 : 855.96 = 387.51 : x
  2. Step 2: Convert to fraction form
    620.25/855.96 = 387.51/x
  3. Step 3: Cross multiply
    620.25x = 855.96 × 387.51
  4. Step 4: Simplify right side
    620.25x = 331,693.06
  5. Step 5: Solve for x
    x = 331,693.06/620.25
  6. Step 6: Final answer
    x = 534.77

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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.