Home / 1,286.16-1,929.32-420.56

Finding the Fourth Proportional to 1,286.16, 1,929.32 and 420.56

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Solution

The fourth proportional to 1,286.16, 1,929.32 and 420.56 is: 630.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.16 : 1,929.32 = 420.56 : x
  2. Step 2: Convert to fraction form
    1,286.16/1,929.32 = 420.56/x
  3. Step 3: Cross multiply
    1,286.16x = 1,929.32 × 420.56
  4. Step 4: Simplify right side
    1,286.16x = 811,394.82
  5. Step 5: Solve for x
    x = 811,394.82/1,286.16
  6. Step 6: Final answer
    x = 630.87

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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.