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Finding the Fourth Proportional to 622.64, 860.34 and 490.20

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Solution

The fourth proportional to 622.64, 860.34 and 490.20 is: 677.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    622.64 : 860.34 = 490.20 : x
  2. Step 2: Convert to fraction form
    622.64/860.34 = 490.20/x
  3. Step 3: Cross multiply
    622.64x = 860.34 × 490.20
  4. Step 4: Simplify right side
    622.64x = 421,738.67
  5. Step 5: Solve for x
    x = 421,738.67/622.64
  6. Step 6: Final answer
    x = 677.34

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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.