Home / 1,286.08-1,929.30-420.46

Finding the Fourth Proportional to 1,286.08, 1,929.30 and 420.46

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Solution

The fourth proportional to 1,286.08, 1,929.30 and 420.46 is: 630.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.08 : 1,929.30 = 420.46 : x
  2. Step 2: Convert to fraction form
    1,286.08/1,929.30 = 420.46/x
  3. Step 3: Cross multiply
    1,286.08x = 1,929.30 × 420.46
  4. Step 4: Simplify right side
    1,286.08x = 811,193.48
  5. Step 5: Solve for x
    x = 811,193.48/1,286.08
  6. Step 6: Final answer
    x = 630.75

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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.