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Finding the Fourth Proportional to 1,389.75, 2,084.76 and 620.25

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Solution

The fourth proportional to 1,389.75, 2,084.76 and 620.25 is: 930.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.75 : 2,084.76 = 620.25 : x
  2. Step 2: Convert to fraction form
    1,389.75/2,084.76 = 620.25/x
  3. Step 3: Cross multiply
    1,389.75x = 2,084.76 × 620.25
  4. Step 4: Simplify right side
    1,389.75x = 1,293,072.39
  5. Step 5: Solve for x
    x = 1,293,072.39/1,389.75
  6. Step 6: Final answer
    x = 930.44

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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.