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Finding the Fourth Proportional to 1,280.00, 1,920.02 and 630.78

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Solution

The fourth proportional to 1,280.00, 1,920.02 and 630.78 is: 946.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.00 : 1,920.02 = 630.78 : x
  2. Step 2: Convert to fraction form
    1,280.00/1,920.02 = 630.78/x
  3. Step 3: Cross multiply
    1,280.00x = 1,920.02 × 630.78
  4. Step 4: Simplify right side
    1,280.00x = 1,211,107.06
  5. Step 5: Solve for x
    x = 1,211,107.06/1,280.00
  6. Step 6: Final answer
    x = 946.18

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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.