Home / 1,353.20-2,029.86-428.78

Finding the Fourth Proportional to 1,353.20, 2,029.86 and 428.78

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Solution

The fourth proportional to 1,353.20, 2,029.86 and 428.78 is: 643.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,353.20 : 2,029.86 = 428.78 : x
  2. Step 2: Convert to fraction form
    1,353.20/2,029.86 = 428.78/x
  3. Step 3: Cross multiply
    1,353.20x = 2,029.86 × 428.78
  4. Step 4: Simplify right side
    1,353.20x = 870,353.22
  5. Step 5: Solve for x
    x = 870,353.22/1,353.20
  6. Step 6: Final answer
    x = 643.18

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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.