Home / 1,286.50-1,929.80-409.60

Finding the Fourth Proportional to 1,286.50, 1,929.80 and 409.60

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Solution

The fourth proportional to 1,286.50, 1,929.80 and 409.60 is: 614.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.50 : 1,929.80 = 409.60 : x
  2. Step 2: Convert to fraction form
    1,286.50/1,929.80 = 409.60/x
  3. Step 3: Cross multiply
    1,286.50x = 1,929.80 × 409.60
  4. Step 4: Simplify right side
    1,286.50x = 790,446.08
  5. Step 5: Solve for x
    x = 790,446.08/1,286.50
  6. Step 6: Final answer
    x = 614.42

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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.