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Finding the Fourth Proportional to 621.89, 859.29 and 511.28

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Solution

The fourth proportional to 621.89, 859.29 and 511.28 is: 706.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.89 : 859.29 = 511.28 : x
  2. Step 2: Convert to fraction form
    621.89/859.29 = 511.28/x
  3. Step 3: Cross multiply
    621.89x = 859.29 × 511.28
  4. Step 4: Simplify right side
    621.89x = 439,337.79
  5. Step 5: Solve for x
    x = 439,337.79/621.89
  6. Step 6: Final answer
    x = 706.46

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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.