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Finding the Fourth Proportional to 511.09, 770.90 and 511.09

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Solution

The fourth proportional to 511.09, 770.90 and 511.09 is: 770.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    511.09 : 770.90 = 511.09 : x
  2. Step 2: Convert to fraction form
    511.09/770.90 = 511.09/x
  3. Step 3: Cross multiply
    511.09x = 770.90 × 511.09
  4. Step 4: Simplify right side
    511.09x = 393,999.28
  5. Step 5: Solve for x
    x = 393,999.28/511.09
  6. Step 6: Final answer
    x = 770.90

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.