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Finding the Fourth Proportional to 620.80, 856.71 and 471.12

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Solution

The fourth proportional to 620.80, 856.71 and 471.12 is: 650.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.80 : 856.71 = 471.12 : x
  2. Step 2: Convert to fraction form
    620.80/856.71 = 471.12/x
  3. Step 3: Cross multiply
    620.80x = 856.71 × 471.12
  4. Step 4: Simplify right side
    620.80x = 403,610.00
  5. Step 5: Solve for x
    x = 403,610.00/620.80
  6. Step 6: Final answer
    x = 650.15

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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.