Home / 1,218.24-1,826.55-639.90

Finding the Fourth Proportional to 1,218.24, 1,826.55 and 639.90

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Solution

The fourth proportional to 1,218.24, 1,826.55 and 639.90 is: 959.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218.24 : 1,826.55 = 639.90 : x
  2. Step 2: Convert to fraction form
    1,218.24/1,826.55 = 639.90/x
  3. Step 3: Cross multiply
    1,218.24x = 1,826.55 × 639.90
  4. Step 4: Simplify right side
    1,218.24x = 1,168,809.35
  5. Step 5: Solve for x
    x = 1,168,809.35/1,218.24
  6. Step 6: Final answer
    x = 959.42

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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.