Home / 1,378.20-2,068.33-648.29

Finding the Fourth Proportional to 1,378.20, 2,068.33 and 648.29

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Solution

The fourth proportional to 1,378.20, 2,068.33 and 648.29 is: 972.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,378.20 : 2,068.33 = 648.29 : x
  2. Step 2: Convert to fraction form
    1,378.20/2,068.33 = 648.29/x
  3. Step 3: Cross multiply
    1,378.20x = 2,068.33 × 648.29
  4. Step 4: Simplify right side
    1,378.20x = 1,340,868.96
  5. Step 5: Solve for x
    x = 1,340,868.96/1,378.20
  6. Step 6: Final answer
    x = 972.91

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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.