Home / 1,315.73-1,971.09-820.69

Finding the Fourth Proportional to 1,315.73, 1,971.09 and 820.69

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Solution

The fourth proportional to 1,315.73, 1,971.09 and 820.69 is: 1,229.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,315.73 : 1,971.09 = 820.69 : x
  2. Step 2: Convert to fraction form
    1,315.73/1,971.09 = 820.69/x
  3. Step 3: Cross multiply
    1,315.73x = 1,971.09 × 820.69
  4. Step 4: Simplify right side
    1,315.73x = 1,617,648.92
  5. Step 5: Solve for x
    x = 1,617,648.92/1,315.73
  6. Step 6: Final answer
    x = 1,229.47

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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.