Home / 1,286.35-1,929.46-420.67

Finding the Fourth Proportional to 1,286.35, 1,929.46 and 420.67

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Solution

The fourth proportional to 1,286.35, 1,929.46 and 420.67 is: 630.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.35 : 1,929.46 = 420.67 : x
  2. Step 2: Convert to fraction form
    1,286.35/1,929.46 = 420.67/x
  3. Step 3: Cross multiply
    1,286.35x = 1,929.46 × 420.67
  4. Step 4: Simplify right side
    1,286.35x = 811,665.94
  5. Step 5: Solve for x
    x = 811,665.94/1,286.35
  6. Step 6: Final answer
    x = 630.98

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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.