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Finding the Fourth Proportional to 620.80, 856.74 and 358.90

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Solution

The fourth proportional to 620.80, 856.74 and 358.90 is: 495.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.80 : 856.74 = 358.90 : x
  2. Step 2: Convert to fraction form
    620.80/856.74 = 358.90/x
  3. Step 3: Cross multiply
    620.80x = 856.74 × 358.90
  4. Step 4: Simplify right side
    620.80x = 307,480.95
  5. Step 5: Solve for x
    x = 307,480.95/620.80
  6. Step 6: Final answer
    x = 495.30

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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.