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Finding the Fourth Proportional to 685.65, 1,028.74 and 300.63

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Solution

The fourth proportional to 685.65, 1,028.74 and 300.63 is: 451.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.65 : 1,028.74 = 300.63 : x
  2. Step 2: Convert to fraction form
    685.65/1,028.74 = 300.63/x
  3. Step 3: Cross multiply
    685.65x = 1,028.74 × 300.63
  4. Step 4: Simplify right side
    685.65x = 309,270.11
  5. Step 5: Solve for x
    x = 309,270.11/685.65
  6. Step 6: Final answer
    x = 451.06

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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.