Home / 1,353.21-2,029.81-428.86

Finding the Fourth Proportional to 1,353.21, 2,029.81 and 428.86

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Solution

The fourth proportional to 1,353.21, 2,029.81 and 428.86 is: 643.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,353.21 : 2,029.81 = 428.86 : x
  2. Step 2: Convert to fraction form
    1,353.21/2,029.81 = 428.86/x
  3. Step 3: Cross multiply
    1,353.21x = 2,029.81 × 428.86
  4. Step 4: Simplify right side
    1,353.21x = 870,498.02
  5. Step 5: Solve for x
    x = 870,498.02/1,353.21
  6. Step 6: Final answer
    x = 643.29

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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.