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Finding the Fourth Proportional to 687.63, 1,028.28 and 512.25

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Solution

The fourth proportional to 687.63, 1,028.28 and 512.25 is: 766.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    687.63 : 1,028.28 = 512.25 : x
  2. Step 2: Convert to fraction form
    687.63/1,028.28 = 512.25/x
  3. Step 3: Cross multiply
    687.63x = 1,028.28 × 512.25
  4. Step 4: Simplify right side
    687.63x = 526,736.43
  5. Step 5: Solve for x
    x = 526,736.43/687.63
  6. Step 6: Final answer
    x = 766.02

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.