Home / 1,638.31-2,455.92-815.81

Finding the Fourth Proportional to 1,638.31, 2,455.92 and 815.81

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Solution

The fourth proportional to 1,638.31, 2,455.92 and 815.81 is: 1,222.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.31 : 2,455.92 = 815.81 : x
  2. Step 2: Convert to fraction form
    1,638.31/2,455.92 = 815.81/x
  3. Step 3: Cross multiply
    1,638.31x = 2,455.92 × 815.81
  4. Step 4: Simplify right side
    1,638.31x = 2,003,551.82
  5. Step 5: Solve for x
    x = 2,003,551.82/1,638.31
  6. Step 6: Final answer
    x = 1,222.94

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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.