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Finding the Fourth Proportional to 689.58, 1,028.23 and 681.08

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Solution

The fourth proportional to 689.58, 1,028.23 and 681.08 is: 1,015.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.58 : 1,028.23 = 681.08 : x
  2. Step 2: Convert to fraction form
    689.58/1,028.23 = 681.08/x
  3. Step 3: Cross multiply
    689.58x = 1,028.23 × 681.08
  4. Step 4: Simplify right side
    689.58x = 700,300.04
  5. Step 5: Solve for x
    x = 700,300.04/689.58
  6. Step 6: Final answer
    x = 1,015.55

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.