Home / 1,399.30-2,099.05-425.40

Finding the Fourth Proportional to 1,399.30, 2,099.05 and 425.40

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Solution

The fourth proportional to 1,399.30, 2,099.05 and 425.40 is: 638.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,399.30 : 2,099.05 = 425.40 : x
  2. Step 2: Convert to fraction form
    1,399.30/2,099.05 = 425.40/x
  3. Step 3: Cross multiply
    1,399.30x = 2,099.05 × 425.40
  4. Step 4: Simplify right side
    1,399.30x = 892,934.81
  5. Step 5: Solve for x
    x = 892,934.81/1,399.30
  6. Step 6: Final answer
    x = 638.13

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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.