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Finding the Fourth Proportional to 620.49, 857.49 and 509.79

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Solution

The fourth proportional to 620.49, 857.49 and 509.79 is: 704.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.49 : 857.49 = 509.79 : x
  2. Step 2: Convert to fraction form
    620.49/857.49 = 509.79/x
  3. Step 3: Cross multiply
    620.49x = 857.49 × 509.79
  4. Step 4: Simplify right side
    620.49x = 437,139.83
  5. Step 5: Solve for x
    x = 437,139.83/620.49
  6. Step 6: Final answer
    x = 704.51

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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.