Home / 1,428.20-2,140.76-648.62

Finding the Fourth Proportional to 1,428.20, 2,140.76 and 648.62

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Solution

The fourth proportional to 1,428.20, 2,140.76 and 648.62 is: 972.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,428.20 : 2,140.76 = 648.62 : x
  2. Step 2: Convert to fraction form
    1,428.20/2,140.76 = 648.62/x
  3. Step 3: Cross multiply
    1,428.20x = 2,140.76 × 648.62
  4. Step 4: Simplify right side
    1,428.20x = 1,388,539.75
  5. Step 5: Solve for x
    x = 1,388,539.75/1,428.20
  6. Step 6: Final answer
    x = 972.23

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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.