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Finding the Fourth Proportional to 685.80, 1,028.88 and 356.76

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Solution

The fourth proportional to 685.80, 1,028.88 and 356.76 is: 535.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.80 : 1,028.88 = 356.76 : x
  2. Step 2: Convert to fraction form
    685.80/1,028.88 = 356.76/x
  3. Step 3: Cross multiply
    685.80x = 1,028.88 × 356.76
  4. Step 4: Simplify right side
    685.80x = 367,063.23
  5. Step 5: Solve for x
    x = 367,063.23/685.80
  6. Step 6: Final answer
    x = 535.23

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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.