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Finding the Fourth Proportional to 620.41, 857.34 and 490.45

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Solution

The fourth proportional to 620.41, 857.34 and 490.45 is: 677.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.41 : 857.34 = 490.45 : x
  2. Step 2: Convert to fraction form
    620.41/857.34 = 490.45/x
  3. Step 3: Cross multiply
    620.41x = 857.34 × 490.45
  4. Step 4: Simplify right side
    620.41x = 420,482.40
  5. Step 5: Solve for x
    x = 420,482.40/620.41
  6. Step 6: Final answer
    x = 677.75

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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.