Home / 1,218.28-1,827.90-640.84

Finding the Fourth Proportional to 1,218.28, 1,827.90 and 640.84

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Solution

The fourth proportional to 1,218.28, 1,827.90 and 640.84 is: 961.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218.28 : 1,827.90 = 640.84 : x
  2. Step 2: Convert to fraction form
    1,218.28/1,827.90 = 640.84/x
  3. Step 3: Cross multiply
    1,218.28x = 1,827.90 × 640.84
  4. Step 4: Simplify right side
    1,218.28x = 1,171,391.44
  5. Step 5: Solve for x
    x = 1,171,391.44/1,218.28
  6. Step 6: Final answer
    x = 961.51

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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.