Home / 1,288.51-1,778.68-868.73

Finding the Fourth Proportional to 1,288.51, 1,778.68 and 868.73

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Solution

The fourth proportional to 1,288.51, 1,778.68 and 868.73 is: 1,199.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,288.51 : 1,778.68 = 868.73 : x
  2. Step 2: Convert to fraction form
    1,288.51/1,778.68 = 868.73/x
  3. Step 3: Cross multiply
    1,288.51x = 1,778.68 × 868.73
  4. Step 4: Simplify right side
    1,288.51x = 1,545,187.31
  5. Step 5: Solve for x
    x = 1,545,187.31/1,288.51
  6. Step 6: Final answer
    x = 1,199.21

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.